Agonist activity at human EP4 receptor expressed in HEK293T/17 cells assessed as increase in GalphaS-mediated CREB activation measured after 6 to 24 hrs by SEAP reporter gene-based chemiluminescence assayAgonist activity at human EP4 receptor expressed in HEK293T/17 cells assessed as increase in GalphaS-mediated CREB activation measured after 6 to 24 hrs by SEAP reporter gene-based chemiluminescence assay

SEAP Activity Assay: 1. Seed cells on an EP2 or EP4 STEP plate at a density of 40,000-80,000 cells/well in 200 ul of reduced serum medium containing 0.5% FBS. Place the plate in a 37° C. incubator with 5% CO2 and incubate overnight. 2. After 16-18 hours of incubation, aspirate the culture media from each well. 3. Add 200 ul of culture medium containing different concentration of test compounds to the assigned wells. For each test compound, at least 8 concentrations starting at highest 10 M and lowest 0.01 pM were tested. In addition each concentration had triplicates. A PGE2 curve (concentrations from lowest to highest, 0 pM, 0.384 pM, 1.92 pM, 9.6 pM, 48 pM, 240 pM, 1200 pM, and 6000 pM) was always run in parallel with test compounds. 4. After 6-8 hours of stimulation with test compounds and PGE2, 10 ul of culture media from each well was transferred to a corresponding well of a 96-well solid black plate. Cover the plate with the lid.SEAP Activity Assay: 1. Seed cells on an EP2 or EP4 STEP plate at a density of 40,000-80,000 cells/well in 200 ul of reduced serum medium containing 0.5% FBS. Place the plate in a 37° C. incubator with 5% CO2 and incubate overnight. 2. After 16-18 hours of incubation, aspirate the culture media from each well. 3. Add 200 ul of culture medium containing different concentration of test compounds to the assigned wells. For each test compound, at least 8 concentrations starting at highest 10 M and lowest 0.01 pM were tested. In addition each concentration had triplicates. A PGE2 curve (concentrations from lowest to highest, 0 pM, 0.384 pM, 1.92 pM, 9.6 pM, 48 pM, 240 pM, 1200 pM, and 6000 pM) was always run in parallel with test compounds. 4. After 6-8 hours of stimulation with test compounds and PGE2, 10 ul of culture media from each well was transferred to a corresponding well of a 96-well solid black plate. Cover the plate with the lid.

cAMP Assay: 1. Seed cells on an EP2 or EP4 STEP plate at a density of 40,000-80,000 cells/well in 200 uL of reduced serum medium containing 0.5% FBS. Place the plate in a 37° C. incubator with 5% CO2 and incubate overnight. 2. After 16-18 hours of incubation, aspirate the culture media from each well. 3. Add 200 ul of culture medium containing 500 uM IBMX (an inhibitor of cAMP phosphodiesterase) and different concentration of test compounds to the assigned wells. For each test compound, at least 8 concentrations starting at highest 10 M and lowest 0.01 pM were tested. In addition each concentration had triplicates. A PGE2 curve (concentrations from lowest to highest, 0 pM, 0.384 pM, 1.92 pM, 9.6 pM, 48 pM, 240 pM, 1200 pM, and 6000 pM) was always run in parallel with test compounds. 4. Incubate the cells in a cell culture incubator for 30 minutes. 5. Centrifuge the plate at 1,000x rpm for 10 minutes. 6. Aspirate the supernatant.cAMP Assay: 1. Seed cells on an EP2 or EP4 STEP plate at a density of 40,000-80,000 cells/well in 200 uL of reduced serum medium containing 0.5% FBS. Place the plate in a 37° C. incubator with 5% CO2 and incubate overnight. 2. After 16-18 hours of incubation, aspirate the culture media from each well. 3. Add 200 ul of culture medium containing 500 uM IBMX (an inhibitor of cAMP phosphodiesterase) and different concentration of test compounds to the assigned wells. For each test compound, at least 8 concentrations starting at highest 10 M and lowest 0.01 pM were tested. In addition each concentration had triplicates. A PGE2 curve (concentrations from lowest to highest, 0 pM, 0.384 pM, 1.92 pM, 9.6 pM, 48 pM, 240 pM, 1200 pM, and 6000 pM) was always run in parallel with test compounds. 4. Incubate the cells in a cell culture incubator for 30 minutes. 5. Centrifuge the plate at 1,000x rpm for 10 minutes. 6. Aspirate the supernatant.

cAMP Assay: 1. Seed cells on an EP2 or EP4 STEP plate at a density of 40,000-80,000 cells/well in 200 uL of reduced serum medium containing 0.5% FBS. Place the plate in a 37° C. incubator with 5% CO2 and incubate overnight. 2. After 16-18 hours of incubation, aspirate the culture media from each well. 3. Add 200 ul of culture medium containing 500 uM IBMX (an inhibitor of cAMP phosphodiesterase) and different concentration of test compounds to the assigned wells. For each test compound, at least 8 concentrations starting at highest 10 M and lowest 0.01 pM were tested. In addition each concentration had triplicates. A PGE2 curve (concentrations from lowest to highest, 0 pM, 0.384 pM, 1.92 pM, 9.6 pM, 48 pM, 240 pM, 1200 pM, and 6000 pM) was always run in parallel with test compounds. 4. Incubate the cells in a cell culture incubator for 30 minutes. 5. Centrifuge the plate at 1,000x rpm for 10 minutes. 6. Aspirate the supernatant.cAMP Assay: 1. Seed cells on an EP2 or EP4 STEP plate at a density of 40,000-80,000 cells/well in 200 uL of reduced serum medium containing 0.5% FBS. Place the plate in a 37° C. incubator with 5% CO2 and incubate overnight. 2. After 16-18 hours of incubation, aspirate the culture media from each well. 3. Add 200 ul of culture medium containing 500 uM IBMX (an inhibitor of cAMP phosphodiesterase) and different concentration of test compounds to the assigned wells. For each test compound, at least 8 concentrations starting at highest 10 M and lowest 0.01 pM were tested. In addition each concentration had triplicates. A PGE2 curve (concentrations from lowest to highest, 0 pM, 0.384 pM, 1.92 pM, 9.6 pM, 48 pM, 240 pM, 1200 pM, and 6000 pM) was always run in parallel with test compounds. 4. Incubate the cells in a cell culture incubator for 30 minutes. 5. Centrifuge the plate at 1,000x rpm for 10 minutes. 6. Aspirate the supernatant.

Agonist activity at human EP4 receptor by cAMP assayAgonist activity at human EP4 receptor by cAMP assay

Agonist activity at human EP4 receptor expressed in HEK293T/17 cells assessed as increase in GalphaS-mediated CREB activation measured after 6 to 24 hrs by SEAP reporter gene-based chemiluminescence assayAgonist activity at human EP4 receptor expressed in HEK293T/17 cells assessed as increase in GalphaS-mediated CREB activation measured after 6 to 24 hrs by SEAP reporter gene-based chemiluminescence assay

Agonist activity at human EP4 receptor expressed in HEK293T/17 cells assessed as increase in GalphaS-mediated CREB activation measured after 6 to 24 hrs by SEAP reporter gene-based chemiluminescence assayAgonist activity at human EP4 receptor expressed in HEK293T/17 cells assessed as increase in GalphaS-mediated CREB activation measured after 6 to 24 hrs by SEAP reporter gene-based chemiluminescence assay

cAMP Assay: 1. Seed cells on an EP2 or EP4 STEP plate at a density of 40,000-80,000 cells/well in 200 uL of reduced serum medium containing 0.5% FBS. Place the plate in a 37° C. incubator with 5% CO2 and incubate overnight. 2. After 16-18 hours of incubation, aspirate the culture media from each well. 3. Add 200 ul of culture medium containing 500 uM IBMX (an inhibitor of cAMP phosphodiesterase) and different concentration of test compounds to the assigned wells. For each test compound, at least 8 concentrations starting at highest 10 M and lowest 0.01 pM were tested. In addition each concentration had triplicates. A PGE2 curve (concentrations from lowest to highest, 0 pM, 0.384 pM, 1.92 pM, 9.6 pM, 48 pM, 240 pM, 1200 pM, and 6000 pM) was always run in parallel with test compounds. 4. Incubate the cells in a cell culture incubator for 30 minutes. 5. Centrifuge the plate at 1,000x rpm for 10 minutes. 6. Aspirate the supernatant.cAMP Assay: 1. Seed cells on an EP2 or EP4 STEP plate at a density of 40,000-80,000 cells/well in 200 uL of reduced serum medium containing 0.5% FBS. Place the plate in a 37° C. incubator with 5% CO2 and incubate overnight. 2. After 16-18 hours of incubation, aspirate the culture media from each well. 3. Add 200 ul of culture medium containing 500 uM IBMX (an inhibitor of cAMP phosphodiesterase) and different concentration of test compounds to the assigned wells. For each test compound, at least 8 concentrations starting at highest 10 M and lowest 0.01 pM were tested. In addition each concentration had triplicates. A PGE2 curve (concentrations from lowest to highest, 0 pM, 0.384 pM, 1.92 pM, 9.6 pM, 48 pM, 240 pM, 1200 pM, and 6000 pM) was always run in parallel with test compounds. 4. Incubate the cells in a cell culture incubator for 30 minutes. 5. Centrifuge the plate at 1,000x rpm for 10 minutes. 6. Aspirate the supernatant.

Agonist activity at human EP4 receptor by cAMP assayAgonist activity at human EP4 receptor by cAMP assay

Agonist activity at human EP4 receptor by cAMP assayAgonist activity at human EP4 receptor by cAMP assay

SEAP Activity Assay: 1. Seed cells on an EP2 or EP4 STEP plate at a density of 40,000-80,000 cells/well in 200 ul of reduced serum medium containing 0.5% FBS. Place the plate in a 37° C. incubator with 5% CO2 and incubate overnight. 2. After 16-18 hours of incubation, aspirate the culture media from each well. 3. Add 200 ul of culture medium containing different concentration of test compounds to the assigned wells. For each test compound, at least 8 concentrations starting at highest 10 M and lowest 0.01 pM were tested. In addition each concentration had triplicates. A PGE2 curve (concentrations from lowest to highest, 0 pM, 0.384 pM, 1.92 pM, 9.6 pM, 48 pM, 240 pM, 1200 pM, and 6000 pM) was always run in parallel with test compounds. 4. After 6-8 hours of stimulation with test compounds and PGE2, 10 ul of culture media from each well was transferred to a corresponding well of a 96-well solid black plate. Cover the plate with the lid.SEAP Activity Assay: 1. Seed cells on an EP2 or EP4 STEP plate at a density of 40,000-80,000 cells/well in 200 ul of reduced serum medium containing 0.5% FBS. Place the plate in a 37° C. incubator with 5% CO2 and incubate overnight. 2. After 16-18 hours of incubation, aspirate the culture media from each well. 3. Add 200 ul of culture medium containing different concentration of test compounds to the assigned wells. For each test compound, at least 8 concentrations starting at highest 10 M and lowest 0.01 pM were tested. In addition each concentration had triplicates. A PGE2 curve (concentrations from lowest to highest, 0 pM, 0.384 pM, 1.92 pM, 9.6 pM, 48 pM, 240 pM, 1200 pM, and 6000 pM) was always run in parallel with test compounds. 4. After 6-8 hours of stimulation with test compounds and PGE2, 10 ul of culture media from each well was transferred to a corresponding well of a 96-well solid black plate. Cover the plate with the lid.

SEAP Activity Assay: 1. Seed cells on an EP2 or EP4 STEP plate at a density of 40,000-80,000 cells/well in 200 ul of reduced serum medium containing 0.5% FBS. Place the plate in a 37° C. incubator with 5% CO2 and incubate overnight. 2. After 16-18 hours of incubation, aspirate the culture media from each well. 3. Add 200 ul of culture medium containing different concentration of test compounds to the assigned wells. For each test compound, at least 8 concentrations starting at highest 10 M and lowest 0.01 pM were tested. In addition each concentration had triplicates. A PGE2 curve (concentrations from lowest to highest, 0 pM, 0.384 pM, 1.92 pM, 9.6 pM, 48 pM, 240 pM, 1200 pM, and 6000 pM) was always run in parallel with test compounds. 4. After 6-8 hours of stimulation with test compounds and PGE2, 10 ul of culture media from each well was transferred to a corresponding well of a 96-well solid black plate. Cover the plate with the lid.SEAP Activity Assay: 1. Seed cells on an EP2 or EP4 STEP plate at a density of 40,000-80,000 cells/well in 200 ul of reduced serum medium containing 0.5% FBS. Place the plate in a 37° C. incubator with 5% CO2 and incubate overnight. 2. After 16-18 hours of incubation, aspirate the culture media from each well. 3. Add 200 ul of culture medium containing different concentration of test compounds to the assigned wells. For each test compound, at least 8 concentrations starting at highest 10 M and lowest 0.01 pM were tested. In addition each concentration had triplicates. A PGE2 curve (concentrations from lowest to highest, 0 pM, 0.384 pM, 1.92 pM, 9.6 pM, 48 pM, 240 pM, 1200 pM, and 6000 pM) was always run in parallel with test compounds. 4. After 6-8 hours of stimulation with test compounds and PGE2, 10 ul of culture media from each well was transferred to a corresponding well of a 96-well solid black plate. Cover the plate with the lid.

cAMP Assay: 1. Seed cells on an EP2 or EP4 STEP plate at a density of 40,000-80,000 cells/well in 200 uL of reduced serum medium containing 0.5% FBS. Place the plate in a 37° C. incubator with 5% CO2 and incubate overnight. 2. After 16-18 hours of incubation, aspirate the culture media from each well. 3. Add 200 ul of culture medium containing 500 uM IBMX (an inhibitor of cAMP phosphodiesterase) and different concentration of test compounds to the assigned wells. For each test compound, at least 8 concentrations starting at highest 10 M and lowest 0.01 pM were tested. In addition each concentration had triplicates. A PGE2 curve (concentrations from lowest to highest, 0 pM, 0.384 pM, 1.92 pM, 9.6 pM, 48 pM, 240 pM, 1200 pM, and 6000 pM) was always run in parallel with test compounds. 4. Incubate the cells in a cell culture incubator for 30 minutes. 5. Centrifuge the plate at 1,000x rpm for 10 minutes. 6. Aspirate the supernatant.cAMP Assay: 1. Seed cells on an EP2 or EP4 STEP plate at a density of 40,000-80,000 cells/well in 200 uL of reduced serum medium containing 0.5% FBS. Place the plate in a 37° C. incubator with 5% CO2 and incubate overnight. 2. After 16-18 hours of incubation, aspirate the culture media from each well. 3. Add 200 ul of culture medium containing 500 uM IBMX (an inhibitor of cAMP phosphodiesterase) and different concentration of test compounds to the assigned wells. For each test compound, at least 8 concentrations starting at highest 10 M and lowest 0.01 pM were tested. In addition each concentration had triplicates. A PGE2 curve (concentrations from lowest to highest, 0 pM, 0.384 pM, 1.92 pM, 9.6 pM, 48 pM, 240 pM, 1200 pM, and 6000 pM) was always run in parallel with test compounds. 4. Incubate the cells in a cell culture incubator for 30 minutes. 5. Centrifuge the plate at 1,000x rpm for 10 minutes. 6. Aspirate the supernatant.

Agonist activity at human EP4 receptor by cAMP assayAgonist activity at human EP4 receptor by cAMP assay

Functional activity at human EP4 receptorFunctional activity at human EP4 receptor

cAMP Assay: A 384-well drug plate was prepared to contain test compounds, PGE2 and cAMP in 16 serial dilutions in triplicate, using a Biomek station. HEK-EBNA cells expressing a target PG receptor subtype (EP2 or EP4) were suspended in a stimulation buffer (HBSS, 0.1% BSA, 0.5 mM IBMX and 5 mM HEPES, pH 7.4) in a density of 104 cells/5 μl. The reaction was initiated by mixing 5 μL drug dilutions with 5 μl of HEK-EBNA cells in a well, carried out for 30 min at room temperature, and followed by the addition of 5 μl anti-cAMP acceptor beads in the control buffer with Tween-20 (25 mM NaCl, 0.03% Tween-20, 5 mM HEPES, pH7.4). After 30 min in the dark at room temperature, the mixtures were incubated with 15 μl biotinylated-cAMP/strpavidin donor beads in Lysis/Detection buffer (0.1% BSA, 0.3% Tween-20 and 5 mM HEPES, pH7.4) for 45 min at the room temperature. Fluorescence changes were read using a Fusion-alpha HT microplate reader.cAMP Assay: A 384-well drug plate was prepared to contain test compounds, PGE2 and cAMP in 16 serial dilutions in triplicate, using a Biomek station. HEK-EBNA cells expressing a target PG receptor subtype (EP2 or EP4) were suspended in a stimulation buffer (HBSS, 0.1% BSA, 0.5 mM IBMX and 5 mM HEPES, pH 7.4) in a density of 104 cells/5 μl. The reaction was initiated by mixing 5 μL drug dilutions with 5 μl of HEK-EBNA cells in a well, carried out for 30 min at room temperature, and followed by the addition of 5 μl anti-cAMP acceptor beads in the control buffer with Tween-20 (25 mM NaCl, 0.03% Tween-20, 5 mM HEPES, pH7.4). After 30 min in the dark at room temperature, the mixtures were incubated with 15 μl biotinylated-cAMP/strpavidin donor beads in Lysis/Detection buffer (0.1% BSA, 0.3% Tween-20 and 5 mM HEPES, pH7.4) for 45 min at the room temperature. Fluorescence changes were read using a Fusion-alpha HT microplate reader.

cAMP Assay: 1. Seed cells on an EP2 or EP4 STEP plate at a density of 40,000-80,000 cells/well in 200 uL of reduced serum medium containing 0.5% FBS. Place the plate in a 37° C. incubator with 5% CO2 and incubate overnight. 2. After 16-18 hours of incubation, aspirate the culture media from each well. 3. Add 200 ul of culture medium containing 500 uM IBMX (an inhibitor of cAMP phosphodiesterase) and different concentration of test compounds to the assigned wells. For each test compound, at least 8 concentrations starting at highest 10 M and lowest 0.01 pM were tested. In addition each concentration had triplicates. A PGE2 curve (concentrations from lowest to highest, 0 pM, 0.384 pM, 1.92 pM, 9.6 pM, 48 pM, 240 pM, 1200 pM, and 6000 pM) was always run in parallel with test compounds. 4. Incubate the cells in a cell culture incubator for 30 minutes. 5. Centrifuge the plate at 1,000x rpm for 10 minutes. 6. Aspirate the supernatant.cAMP Assay: 1. Seed cells on an EP2 or EP4 STEP plate at a density of 40,000-80,000 cells/well in 200 uL of reduced serum medium containing 0.5% FBS. Place the plate in a 37° C. incubator with 5% CO2 and incubate overnight. 2. After 16-18 hours of incubation, aspirate the culture media from each well. 3. Add 200 ul of culture medium containing 500 uM IBMX (an inhibitor of cAMP phosphodiesterase) and different concentration of test compounds to the assigned wells. For each test compound, at least 8 concentrations starting at highest 10 M and lowest 0.01 pM were tested. In addition each concentration had triplicates. A PGE2 curve (concentrations from lowest to highest, 0 pM, 0.384 pM, 1.92 pM, 9.6 pM, 48 pM, 240 pM, 1200 pM, and 6000 pM) was always run in parallel with test compounds. 4. Incubate the cells in a cell culture incubator for 30 minutes. 5. Centrifuge the plate at 1,000x rpm for 10 minutes. 6. Aspirate the supernatant.

SEAP Activity Assay: 1. Seed cells on an EP2 or EP4 STEP plate at a density of 40,000-80,000 cells/well in 200 ul of reduced serum medium containing 0.5% FBS. Place the plate in a 37° C. incubator with 5% CO2 and incubate overnight. 2. After 16-18 hours of incubation, aspirate the culture media from each well. 3. Add 200 ul of culture medium containing different concentration of test compounds to the assigned wells. For each test compound, at least 8 concentrations starting at highest 10 M and lowest 0.01 pM were tested. In addition each concentration had triplicates. A PGE2 curve (concentrations from lowest to highest, 0 pM, 0.384 pM, 1.92 pM, 9.6 pM, 48 pM, 240 pM, 1200 pM, and 6000 pM) was always run in parallel with test compounds. 4. After 6-8 hours of stimulation with test compounds and PGE2, 10 ul of culture media from each well was transferred to a corresponding well of a 96-well solid black plate. Cover the plate with the lid.SEAP Activity Assay: 1. Seed cells on an EP2 or EP4 STEP plate at a density of 40,000-80,000 cells/well in 200 ul of reduced serum medium containing 0.5% FBS. Place the plate in a 37° C. incubator with 5% CO2 and incubate overnight. 2. After 16-18 hours of incubation, aspirate the culture media from each well. 3. Add 200 ul of culture medium containing different concentration of test compounds to the assigned wells. For each test compound, at least 8 concentrations starting at highest 10 M and lowest 0.01 pM were tested. In addition each concentration had triplicates. A PGE2 curve (concentrations from lowest to highest, 0 pM, 0.384 pM, 1.92 pM, 9.6 pM, 48 pM, 240 pM, 1200 pM, and 6000 pM) was always run in parallel with test compounds. 4. After 6-8 hours of stimulation with test compounds and PGE2, 10 ul of culture media from each well was transferred to a corresponding well of a 96-well solid black plate. Cover the plate with the lid.

cAMP Assay: A 384-well drug plate was prepared to contain test compounds, PGE2 and cAMP in 16 serial dilutions in triplicate, using a Biomek station. HEK-EBNA cells expressing a target PG receptor subtype (EP2 or EP4) were suspended in a stimulation buffer (HBSS, 0.1% BSA, 0.5 mM IBMX and 5 mM HEPES, pH 7.4) in a density of 104 cells/5 μl. The reaction was initiated by mixing 5 μL drug dilutions with 5 μl of HEK-EBNA cells in a well, carried out for 30 min at room temperature, and followed by the addition of 5 μl anti-cAMP acceptor beads in the control buffer with Tween-20 (25 mM NaCl, 0.03% Tween-20, 5 mM HEPES, pH7.4). After 30 min in the dark at room temperature, the mixtures were incubated with 15 μl biotinylated-cAMP/strpavidin donor beads in Lysis/Detection buffer (0.1% BSA, 0.3% Tween-20 and 5 mM HEPES, pH7.4) for 45 min at the room temperature. Fluorescence changes were read using a Fusion-alpha HT microplate reader.cAMP Assay: A 384-well drug plate was prepared to contain test compounds, PGE2 and cAMP in 16 serial dilutions in triplicate, using a Biomek station. HEK-EBNA cells expressing a target PG receptor subtype (EP2 or EP4) were suspended in a stimulation buffer (HBSS, 0.1% BSA, 0.5 mM IBMX and 5 mM HEPES, pH 7.4) in a density of 104 cells/5 μl. The reaction was initiated by mixing 5 μL drug dilutions with 5 μl of HEK-EBNA cells in a well, carried out for 30 min at room temperature, and followed by the addition of 5 μl anti-cAMP acceptor beads in the control buffer with Tween-20 (25 mM NaCl, 0.03% Tween-20, 5 mM HEPES, pH7.4). After 30 min in the dark at room temperature, the mixtures were incubated with 15 μl biotinylated-cAMP/strpavidin donor beads in Lysis/Detection buffer (0.1% BSA, 0.3% Tween-20 and 5 mM HEPES, pH7.4) for 45 min at the room temperature. Fluorescence changes were read using a Fusion-alpha HT microplate reader.

SEAP Activity Assay: 1. Seed cells on an EP2 or EP4 STEP plate at a density of 40,000-80,000 cells/well in 200 ul of reduced serum medium containing 0.5% FBS. Place the plate in a 37° C. incubator with 5% CO2 and incubate overnight. 2. After 16-18 hours of incubation, aspirate the culture media from each well. 3. Add 200 ul of culture medium containing different concentration of test compounds to the assigned wells. For each test compound, at least 8 concentrations starting at highest 10 M and lowest 0.01 pM were tested. In addition each concentration had triplicates. A PGE2 curve (concentrations from lowest to highest, 0 pM, 0.384 pM, 1.92 pM, 9.6 pM, 48 pM, 240 pM, 1200 pM, and 6000 pM) was always run in parallel with test compounds. 4. After 6-8 hours of stimulation with test compounds and PGE2, 10 ul of culture media from each well was transferred to a corresponding well of a 96-well solid black plate. Cover the plate with the lid.SEAP Activity Assay: 1. Seed cells on an EP2 or EP4 STEP plate at a density of 40,000-80,000 cells/well in 200 ul of reduced serum medium containing 0.5% FBS. Place the plate in a 37° C. incubator with 5% CO2 and incubate overnight. 2. After 16-18 hours of incubation, aspirate the culture media from each well. 3. Add 200 ul of culture medium containing different concentration of test compounds to the assigned wells. For each test compound, at least 8 concentrations starting at highest 10 M and lowest 0.01 pM were tested. In addition each concentration had triplicates. A PGE2 curve (concentrations from lowest to highest, 0 pM, 0.384 pM, 1.92 pM, 9.6 pM, 48 pM, 240 pM, 1200 pM, and 6000 pM) was always run in parallel with test compounds. 4. After 6-8 hours of stimulation with test compounds and PGE2, 10 ul of culture media from each well was transferred to a corresponding well of a 96-well solid black plate. Cover the plate with the lid.

SEAP Activity Assay: 1. Seed cells on an EP2 or EP4 STEP plate at a density of 40,000-80,000 cells/well in 200 ul of reduced serum medium containing 0.5% FBS. Place the plate in a 37° C. incubator with 5% CO2 and incubate overnight. 2. After 16-18 hours of incubation, aspirate the culture media from each well. 3. Add 200 ul of culture medium containing different concentration of test compounds to the assigned wells. For each test compound, at least 8 concentrations starting at highest 10 M and lowest 0.01 pM were tested. In addition each concentration had triplicates. A PGE2 curve (concentrations from lowest to highest, 0 pM, 0.384 pM, 1.92 pM, 9.6 pM, 48 pM, 240 pM, 1200 pM, and 6000 pM) was always run in parallel with test compounds. 4. After 6-8 hours of stimulation with test compounds and PGE2, 10 ul of culture media from each well was transferred to a corresponding well of a 96-well solid black plate. Cover the plate with the lid.SEAP Activity Assay: 1. Seed cells on an EP2 or EP4 STEP plate at a density of 40,000-80,000 cells/well in 200 ul of reduced serum medium containing 0.5% FBS. Place the plate in a 37° C. incubator with 5% CO2 and incubate overnight. 2. After 16-18 hours of incubation, aspirate the culture media from each well. 3. Add 200 ul of culture medium containing different concentration of test compounds to the assigned wells. For each test compound, at least 8 concentrations starting at highest 10 M and lowest 0.01 pM were tested. In addition each concentration had triplicates. A PGE2 curve (concentrations from lowest to highest, 0 pM, 0.384 pM, 1.92 pM, 9.6 pM, 48 pM, 240 pM, 1200 pM, and 6000 pM) was always run in parallel with test compounds. 4. After 6-8 hours of stimulation with test compounds and PGE2, 10 ul of culture media from each well was transferred to a corresponding well of a 96-well solid black plate. Cover the plate with the lid.

cAMP Assay: 1. Seed cells on an EP2 or EP4 STEP plate at a density of 40,000-80,000 cells/well in 200 uL of reduced serum medium containing 0.5% FBS. Place the plate in a 37° C. incubator with 5% CO2 and incubate overnight. 2. After 16-18 hours of incubation, aspirate the culture media from each well. 3. Add 200 ul of culture medium containing 500 uM IBMX (an inhibitor of cAMP phosphodiesterase) and different concentration of test compounds to the assigned wells. For each test compound, at least 8 concentrations starting at highest 10 M and lowest 0.01 pM were tested. In addition each concentration had triplicates. A PGE2 curve (concentrations from lowest to highest, 0 pM, 0.384 pM, 1.92 pM, 9.6 pM, 48 pM, 240 pM, 1200 pM, and 6000 pM) was always run in parallel with test compounds. 4. Incubate the cells in a cell culture incubator for 30 minutes. 5. Centrifuge the plate at 1,000x rpm for 10 minutes. 6. Aspirate the supernatant.cAMP Assay: 1. Seed cells on an EP2 or EP4 STEP plate at a density of 40,000-80,000 cells/well in 200 uL of reduced serum medium containing 0.5% FBS. Place the plate in a 37° C. incubator with 5% CO2 and incubate overnight. 2. After 16-18 hours of incubation, aspirate the culture media from each well. 3. Add 200 ul of culture medium containing 500 uM IBMX (an inhibitor of cAMP phosphodiesterase) and different concentration of test compounds to the assigned wells. For each test compound, at least 8 concentrations starting at highest 10 M and lowest 0.01 pM were tested. In addition each concentration had triplicates. A PGE2 curve (concentrations from lowest to highest, 0 pM, 0.384 pM, 1.92 pM, 9.6 pM, 48 pM, 240 pM, 1200 pM, and 6000 pM) was always run in parallel with test compounds. 4. Incubate the cells in a cell culture incubator for 30 minutes. 5. Centrifuge the plate at 1,000x rpm for 10 minutes. 6. Aspirate the supernatant.

SEAP Activity Assay: 1. Seed cells on an EP2 or EP4 STEP plate at a density of 40,000-80,000 cells/well in 200 ul of reduced serum medium containing 0.5% FBS. Place the plate in a 37° C. incubator with 5% CO2 and incubate overnight. 2. After 16-18 hours of incubation, aspirate the culture media from each well. 3. Add 200 ul of culture medium containing different concentration of test compounds to the assigned wells. For each test compound, at least 8 concentrations starting at highest 10 M and lowest 0.01 pM were tested. In addition each concentration had triplicates. A PGE2 curve (concentrations from lowest to highest, 0 pM, 0.384 pM, 1.92 pM, 9.6 pM, 48 pM, 240 pM, 1200 pM, and 6000 pM) was always run in parallel with test compounds. 4. After 6-8 hours of stimulation with test compounds and PGE2, 10 ul of culture media from each well was transferred to a corresponding well of a 96-well solid black plate. Cover the plate with the lid.SEAP Activity Assay: 1. Seed cells on an EP2 or EP4 STEP plate at a density of 40,000-80,000 cells/well in 200 ul of reduced serum medium containing 0.5% FBS. Place the plate in a 37° C. incubator with 5% CO2 and incubate overnight. 2. After 16-18 hours of incubation, aspirate the culture media from each well. 3. Add 200 ul of culture medium containing different concentration of test compounds to the assigned wells. For each test compound, at least 8 concentrations starting at highest 10 M and lowest 0.01 pM were tested. In addition each concentration had triplicates. A PGE2 curve (concentrations from lowest to highest, 0 pM, 0.384 pM, 1.92 pM, 9.6 pM, 48 pM, 240 pM, 1200 pM, and 6000 pM) was always run in parallel with test compounds. 4. After 6-8 hours of stimulation with test compounds and PGE2, 10 ul of culture media from each well was transferred to a corresponding well of a 96-well solid black plate. Cover the plate with the lid.

Agonist activity at human EP4 receptor expressed in HEK293T/17 cells assessed as increase in GalphaS-mediated CREB activation measured after 6 to 24 hrs by SEAP reporter gene-based chemiluminescence assayAgonist activity at human EP4 receptor expressed in HEK293T/17 cells assessed as increase in GalphaS-mediated CREB activation measured after 6 to 24 hrs by SEAP reporter gene-based chemiluminescence assay

SEAP Activity Assay: 1. Seed cells on an EP2 or EP4 STEP plate at a density of 40,000-80,000 cells/well in 200 ul of reduced serum medium containing 0.5% FBS. Place the plate in a 37° C. incubator with 5% CO2 and incubate overnight. 2. After 16-18 hours of incubation, aspirate the culture media from each well. 3. Add 200 ul of culture medium containing different concentration of test compounds to the assigned wells. For each test compound, at least 8 concentrations starting at highest 10 M and lowest 0.01 pM were tested. In addition each concentration had triplicates. A PGE2 curve (concentrations from lowest to highest, 0 pM, 0.384 pM, 1.92 pM, 9.6 pM, 48 pM, 240 pM, 1200 pM, and 6000 pM) was always run in parallel with test compounds. 4. After 6-8 hours of stimulation with test compounds and PGE2, 10 ul of culture media from each well was transferred to a corresponding well of a 96-well solid black plate. Cover the plate with the lid.SEAP Activity Assay: 1. Seed cells on an EP2 or EP4 STEP plate at a density of 40,000-80,000 cells/well in 200 ul of reduced serum medium containing 0.5% FBS. Place the plate in a 37° C. incubator with 5% CO2 and incubate overnight. 2. After 16-18 hours of incubation, aspirate the culture media from each well. 3. Add 200 ul of culture medium containing different concentration of test compounds to the assigned wells. For each test compound, at least 8 concentrations starting at highest 10 M and lowest 0.01 pM were tested. In addition each concentration had triplicates. A PGE2 curve (concentrations from lowest to highest, 0 pM, 0.384 pM, 1.92 pM, 9.6 pM, 48 pM, 240 pM, 1200 pM, and 6000 pM) was always run in parallel with test compounds. 4. After 6-8 hours of stimulation with test compounds and PGE2, 10 ul of culture media from each well was transferred to a corresponding well of a 96-well solid black plate. Cover the plate with the lid.

cAMP Assay: 1. Seed cells on an EP2 or EP4 STEP plate at a density of 40,000-80,000 cells/well in 200 uL of reduced serum medium containing 0.5% FBS. Place the plate in a 37° C. incubator with 5% CO2 and incubate overnight. 2. After 16-18 hours of incubation, aspirate the culture media from each well. 3. Add 200 ul of culture medium containing 500 uM IBMX (an inhibitor of cAMP phosphodiesterase) and different concentration of test compounds to the assigned wells. For each test compound, at least 8 concentrations starting at highest 10 M and lowest 0.01 pM were tested. In addition each concentration had triplicates. A PGE2 curve (concentrations from lowest to highest, 0 pM, 0.384 pM, 1.92 pM, 9.6 pM, 48 pM, 240 pM, 1200 pM, and 6000 pM) was always run in parallel with test compounds. 4. Incubate the cells in a cell culture incubator for 30 minutes. 5. Centrifuge the plate at 1,000x rpm for 10 minutes. 6. Aspirate the supernatant.cAMP Assay: 1. Seed cells on an EP2 or EP4 STEP plate at a density of 40,000-80,000 cells/well in 200 uL of reduced serum medium containing 0.5% FBS. Place the plate in a 37° C. incubator with 5% CO2 and incubate overnight. 2. After 16-18 hours of incubation, aspirate the culture media from each well. 3. Add 200 ul of culture medium containing 500 uM IBMX (an inhibitor of cAMP phosphodiesterase) and different concentration of test compounds to the assigned wells. For each test compound, at least 8 concentrations starting at highest 10 M and lowest 0.01 pM were tested. In addition each concentration had triplicates. A PGE2 curve (concentrations from lowest to highest, 0 pM, 0.384 pM, 1.92 pM, 9.6 pM, 48 pM, 240 pM, 1200 pM, and 6000 pM) was always run in parallel with test compounds. 4. Incubate the cells in a cell culture incubator for 30 minutes. 5. Centrifuge the plate at 1,000x rpm for 10 minutes. 6. Aspirate the supernatant.

Agonist activity at human EP4 receptor expressed in HEK293T/17 cells assessed as increase in GalphaS-mediated CREB activation measured after 6 to 24 hrs by SEAP reporter gene-based chemiluminescence assayAgonist activity at human EP4 receptor expressed in HEK293T/17 cells assessed as increase in GalphaS-mediated CREB activation measured after 6 to 24 hrs by SEAP reporter gene-based chemiluminescence assay

Agonist activity at EP4 receptor expressed in HEK293 cells assessed as cAMP accumulationAgonist activity at EP4 receptor expressed in HEK293 cells assessed as cAMP accumulation

Agonist activity at human prostaglandin EP4 receptorAgonist activity at human prostaglandin EP4 receptor

Radioligand Binding: HEK-293 cells stably expressing the human or feline FP receptor, or EP1, EP2, EP3, or EP4 receptors were washed with TME buffer, scraped from the bottom of the flasks, and homogenized for 30 sec using a Brinkman PT 10/35 polytron. TME buffer was added to achieve a final 40 ml volume in the centrifuge tubes (the composition of TME is 100 mM TRIS base, 20 mM MgCl2, 2M EDTA; 10 N HCl is added to achieve a pH of 7.4).The cell homogenate was centrifuged at 19000 r.p.m. for 20 min at 4 C. using a Beckman Ti-60 rotor. The resultant pellet was resuspended in TME buffer to give a final 1 mg/ml protein concentration, as determined by Biorad assay. Radioligand binding competition assays vs. [3H-]17-phenyl PGF2 (5 nM) were performed in a 100 ul volume for 60 min. Binding reactions were started by adding plasma membrane fraction. The reaction was terminated by the addition of 4 ml ice-cold TRIS-HCl buffer and rapid filtration through glass fiber GF/B filters using a Brandel cell.Radioligand Binding: HEK-293 cells stably expressing the human or feline FP receptor, or EP1, EP2, EP3, or EP4 receptors were washed with TME buffer, scraped from the bottom of the flasks, and homogenized for 30 sec using a Brinkman PT 10/35 polytron. TME buffer was added to achieve a final 40 ml volume in the centrifuge tubes (the composition of TME is 100 mM TRIS base, 20 mM MgCl2, 2M EDTA; 10 N HCl is added to achieve a pH of 7.4).The cell homogenate was centrifuged at 19000 r.p.m. for 20 min at 4 C. using a Beckman Ti-60 rotor. The resultant pellet was resuspended in TME buffer to give a final 1 mg/ml protein concentration, as determined by Biorad assay. Radioligand binding competition assays vs. [3H-]17-phenyl PGF2 (5 nM) were performed in a 100 ul volume for 60 min. Binding reactions were started by adding plasma membrane fraction. The reaction was terminated by the addition of 4 ml ice-cold TRIS-HCl buffer and rapid filtration through glass fiber GF/B filters using a Brandel cell.

SEAP Activity Assay: 1. Seed cells on an EP2 or EP4 STEP plate at a density of 40,000-80,000 cells/well in 200 ul of reduced serum medium containing 0.5% FBS. Place the plate in a 37° C. incubator with 5% CO2 and incubate overnight. 2. After 16-18 hours of incubation, aspirate the culture media from each well. 3. Add 200 ul of culture medium containing different concentration of test compounds to the assigned wells. For each test compound, at least 8 concentrations starting at highest 10 M and lowest 0.01 pM were tested. In addition each concentration had triplicates. A PGE2 curve (concentrations from lowest to highest, 0 pM, 0.384 pM, 1.92 pM, 9.6 pM, 48 pM, 240 pM, 1200 pM, and 6000 pM) was always run in parallel with test compounds. 4. After 6-8 hours of stimulation with test compounds and PGE2, 10 ul of culture media from each well was transferred to a corresponding well of a 96-well solid black plate. Cover the plate with the lid.SEAP Activity Assay: 1. Seed cells on an EP2 or EP4 STEP plate at a density of 40,000-80,000 cells/well in 200 ul of reduced serum medium containing 0.5% FBS. Place the plate in a 37° C. incubator with 5% CO2 and incubate overnight. 2. After 16-18 hours of incubation, aspirate the culture media from each well. 3. Add 200 ul of culture medium containing different concentration of test compounds to the assigned wells. For each test compound, at least 8 concentrations starting at highest 10 M and lowest 0.01 pM were tested. In addition each concentration had triplicates. A PGE2 curve (concentrations from lowest to highest, 0 pM, 0.384 pM, 1.92 pM, 9.6 pM, 48 pM, 240 pM, 1200 pM, and 6000 pM) was always run in parallel with test compounds. 4. After 6-8 hours of stimulation with test compounds and PGE2, 10 ul of culture media from each well was transferred to a corresponding well of a 96-well solid black plate. Cover the plate with the lid.

Agonist activity at human EP4 receptor expressed in HEK293T/17 cells assessed as increase in intracellular cAMP level incubated for 30 mins by ELISAAgonist activity at human EP4 receptor expressed in HEK293T/17 cells assessed as increase in intracellular cAMP level incubated for 30 mins by ELISA

cAMP Assay: 1. Seed cells on an EP2 or EP4 STEP plate at a density of 40,000-80,000 cells/well in 200 uL of reduced serum medium containing 0.5% FBS. Place the plate in a 37° C. incubator with 5% CO2 and incubate overnight. 2. After 16-18 hours of incubation, aspirate the culture media from each well. 3. Add 200 ul of culture medium containing 500 uM IBMX (an inhibitor of cAMP phosphodiesterase) and different concentration of test compounds to the assigned wells. For each test compound, at least 8 concentrations starting at highest 10 M and lowest 0.01 pM were tested. In addition each concentration had triplicates. A PGE2 curve (concentrations from lowest to highest, 0 pM, 0.384 pM, 1.92 pM, 9.6 pM, 48 pM, 240 pM, 1200 pM, and 6000 pM) was always run in parallel with test compounds. 4. Incubate the cells in a cell culture incubator for 30 minutes. 5. Centrifuge the plate at 1,000x rpm for 10 minutes. 6. Aspirate the supernatant.cAMP Assay: 1. Seed cells on an EP2 or EP4 STEP plate at a density of 40,000-80,000 cells/well in 200 uL of reduced serum medium containing 0.5% FBS. Place the plate in a 37° C. incubator with 5% CO2 and incubate overnight. 2. After 16-18 hours of incubation, aspirate the culture media from each well. 3. Add 200 ul of culture medium containing 500 uM IBMX (an inhibitor of cAMP phosphodiesterase) and different concentration of test compounds to the assigned wells. For each test compound, at least 8 concentrations starting at highest 10 M and lowest 0.01 pM were tested. In addition each concentration had triplicates. A PGE2 curve (concentrations from lowest to highest, 0 pM, 0.384 pM, 1.92 pM, 9.6 pM, 48 pM, 240 pM, 1200 pM, and 6000 pM) was always run in parallel with test compounds. 4. Incubate the cells in a cell culture incubator for 30 minutes. 5. Centrifuge the plate at 1,000x rpm for 10 minutes. 6. Aspirate the supernatant.

cAMP Assay: 1. Seed cells on an EP2 or EP4 STEP plate at a density of 40,000-80,000 cells/well in 200 uL of reduced serum medium containing 0.5% FBS. Place the plate in a 37° C. incubator with 5% CO2 and incubate overnight. 2. After 16-18 hours of incubation, aspirate the culture media from each well. 3. Add 200 ul of culture medium containing 500 uM IBMX (an inhibitor of cAMP phosphodiesterase) and different concentration of test compounds to the assigned wells. For each test compound, at least 8 concentrations starting at highest 10 M and lowest 0.01 pM were tested. In addition each concentration had triplicates. A PGE2 curve (concentrations from lowest to highest, 0 pM, 0.384 pM, 1.92 pM, 9.6 pM, 48 pM, 240 pM, 1200 pM, and 6000 pM) was always run in parallel with test compounds. 4. Incubate the cells in a cell culture incubator for 30 minutes. 5. Centrifuge the plate at 1,000x rpm for 10 minutes. 6. Aspirate the supernatant.cAMP Assay: 1. Seed cells on an EP2 or EP4 STEP plate at a density of 40,000-80,000 cells/well in 200 uL of reduced serum medium containing 0.5% FBS. Place the plate in a 37° C. incubator with 5% CO2 and incubate overnight. 2. After 16-18 hours of incubation, aspirate the culture media from each well. 3. Add 200 ul of culture medium containing 500 uM IBMX (an inhibitor of cAMP phosphodiesterase) and different concentration of test compounds to the assigned wells. For each test compound, at least 8 concentrations starting at highest 10 M and lowest 0.01 pM were tested. In addition each concentration had triplicates. A PGE2 curve (concentrations from lowest to highest, 0 pM, 0.384 pM, 1.92 pM, 9.6 pM, 48 pM, 240 pM, 1200 pM, and 6000 pM) was always run in parallel with test compounds. 4. Incubate the cells in a cell culture incubator for 30 minutes. 5. Centrifuge the plate at 1,000x rpm for 10 minutes. 6. Aspirate the supernatant.

Agonist activity at human prostaglandin EP4 receptorAgonist activity at human prostaglandin EP4 receptor

Agonist activity at human prostaglandin EP4 receptorAgonist activity at human prostaglandin EP4 receptor

Agonist activity at human prostanoid EP4 receptor expressed in HEK293 cells assessed as potentiation of PGE2-induced cAMP accumulation by scintillation proximity assayAgonist activity at human prostanoid EP4 receptor expressed in HEK293 cells assessed as potentiation of PGE2-induced cAMP accumulation by scintillation proximity assay

Functional activity at human EP4 receptorFunctional activity at human EP4 receptor

Radioligand Binding: HEK-293 cells stably expressing the human or feline FP receptor, or EP1, EP2, EP3, or EP4 receptors were washed with TME buffer, scraped from the bottom of the flasks, and homogenized for 30 sec using a Brinkman PT 10/35 polytron. TME buffer was added to achieve a final 40 ml volume in the centrifuge tubes (the composition of TME is 100 mM TRIS base, 20 mM MgCl2, 2M EDTA; 10 N HCl is added to achieve a pH of 7.4).The cell homogenate was centrifuged at 19000 r.p.m. for 20 min at 4 C. using a Beckman Ti-60 rotor. The resultant pellet was resuspended in TME buffer to give a final 1 mg/ml protein concentration, as determined by Biorad assay. Radioligand binding competition assays vs. [3H-]17-phenyl PGF2 (5 nM) were performed in a 100 ul volume for 60 min. Binding reactions were started by adding plasma membrane fraction. The reaction was terminated by the addition of 4 ml ice-cold TRIS-HCl buffer and rapid filtration through glass fiber GF/B filters using a Brandel cell.Radioligand Binding: HEK-293 cells stably expressing the human or feline FP receptor, or EP1, EP2, EP3, or EP4 receptors were washed with TME buffer, scraped from the bottom of the flasks, and homogenized for 30 sec using a Brinkman PT 10/35 polytron. TME buffer was added to achieve a final 40 ml volume in the centrifuge tubes (the composition of TME is 100 mM TRIS base, 20 mM MgCl2, 2M EDTA; 10 N HCl is added to achieve a pH of 7.4).The cell homogenate was centrifuged at 19000 r.p.m. for 20 min at 4 C. using a Beckman Ti-60 rotor. The resultant pellet was resuspended in TME buffer to give a final 1 mg/ml protein concentration, as determined by Biorad assay. Radioligand binding competition assays vs. [3H-]17-phenyl PGF2 (5 nM) were performed in a 100 ul volume for 60 min. Binding reactions were started by adding plasma membrane fraction. The reaction was terminated by the addition of 4 ml ice-cold TRIS-HCl buffer and rapid filtration through glass fiber GF/B filters using a Brandel cell.

cAMP Assay: A 384-well drug plate was prepared to contain test compounds, PGE2 and cAMP in 16 serial dilutions in triplicate, using a Biomek station. HEK-EBNA cells expressing a target PG receptor subtype (EP2 or EP4) were suspended in a stimulation buffer (HBSS, 0.1% BSA, 0.5 mM IBMX and 5 mM HEPES, pH 7.4) in a density of 104 cells/5 μl. The reaction was initiated by mixing 5 μL drug dilutions with 5 μl of HEK-EBNA cells in a well, carried out for 30 min at room temperature, and followed by the addition of 5 μl anti-cAMP acceptor beads in the control buffer with Tween-20 (25 mM NaCl, 0.03% Tween-20, 5 mM HEPES, pH7.4). After 30 min in the dark at room temperature, the mixtures were incubated with 15 μl biotinylated-cAMP/strpavidin donor beads in Lysis/Detection buffer (0.1% BSA, 0.3% Tween-20 and 5 mM HEPES, pH7.4) for 45 min at the room temperature. Fluorescence changes were read using a Fusion-alpha HT microplate reader.cAMP Assay: A 384-well drug plate was prepared to contain test compounds, PGE2 and cAMP in 16 serial dilutions in triplicate, using a Biomek station. HEK-EBNA cells expressing a target PG receptor subtype (EP2 or EP4) were suspended in a stimulation buffer (HBSS, 0.1% BSA, 0.5 mM IBMX and 5 mM HEPES, pH 7.4) in a density of 104 cells/5 μl. The reaction was initiated by mixing 5 μL drug dilutions with 5 μl of HEK-EBNA cells in a well, carried out for 30 min at room temperature, and followed by the addition of 5 μl anti-cAMP acceptor beads in the control buffer with Tween-20 (25 mM NaCl, 0.03% Tween-20, 5 mM HEPES, pH7.4). After 30 min in the dark at room temperature, the mixtures were incubated with 15 μl biotinylated-cAMP/strpavidin donor beads in Lysis/Detection buffer (0.1% BSA, 0.3% Tween-20 and 5 mM HEPES, pH7.4) for 45 min at the room temperature. Fluorescence changes were read using a Fusion-alpha HT microplate reader.

cAMP Assay: A 384-well drug plate was prepared to contain test compounds, PGE2 and cAMP in 16 serial dilutions in triplicate, using a Biomek station. HEK-EBNA cells expressing a target PG receptor subtype (EP2 or EP4) were suspended in a stimulation buffer (HBSS, 0.1% BSA, 0.5 mM IBMX and 5 mM HEPES, pH 7.4) in a density of 104 cells/5 μl. The reaction was initiated by mixing 5 μL drug dilutions with 5 μl of HEK-EBNA cells in a well, carried out for 30 min at room temperature, and followed by the addition of 5 μl anti-cAMP acceptor beads in the control buffer with Tween-20 (25 mM NaCl, 0.03% Tween-20, 5 mM HEPES, pH7.4). After 30 min in the dark at room temperature, the mixtures were incubated with 15 μl biotinylated-cAMP/strpavidin donor beads in Lysis/Detection buffer (0.1% BSA, 0.3% Tween-20 and 5 mM HEPES, pH7.4) for 45 min at the room temperature. Fluorescence changes were read using a Fusion-alpha HT microplate reader.cAMP Assay: A 384-well drug plate was prepared to contain test compounds, PGE2 and cAMP in 16 serial dilutions in triplicate, using a Biomek station. HEK-EBNA cells expressing a target PG receptor subtype (EP2 or EP4) were suspended in a stimulation buffer (HBSS, 0.1% BSA, 0.5 mM IBMX and 5 mM HEPES, pH 7.4) in a density of 104 cells/5 μl. The reaction was initiated by mixing 5 μL drug dilutions with 5 μl of HEK-EBNA cells in a well, carried out for 30 min at room temperature, and followed by the addition of 5 μl anti-cAMP acceptor beads in the control buffer with Tween-20 (25 mM NaCl, 0.03% Tween-20, 5 mM HEPES, pH7.4). After 30 min in the dark at room temperature, the mixtures were incubated with 15 μl biotinylated-cAMP/strpavidin donor beads in Lysis/Detection buffer (0.1% BSA, 0.3% Tween-20 and 5 mM HEPES, pH7.4) for 45 min at the room temperature. Fluorescence changes were read using a Fusion-alpha HT microplate reader.

cAMP Assay: A 384-well drug plate was prepared to contain test compounds, PGE2 and cAMP in 16 serial dilutions in triplicate, using a Biomek station. HEK-EBNA cells expressing a target PG receptor subtype (EP2 or EP4) were suspended in a stimulation buffer (HBSS, 0.1% BSA, 0.5 mM IBMX and 5 mM HEPES, pH 7.4) in a density of 104 cells/5 μl. The reaction was initiated by mixing 5 μL drug dilutions with 5 μl of HEK-EBNA cells in a well, carried out for 30 min at room temperature, and followed by the addition of 5 μl anti-cAMP acceptor beads in the control buffer with Tween-20 (25 mM NaCl, 0.03% Tween-20, 5 mM HEPES, pH7.4). After 30 min in the dark at room temperature, the mixtures were incubated with 15 μl biotinylated-cAMP/strpavidin donor beads in Lysis/Detection buffer (0.1% BSA, 0.3% Tween-20 and 5 mM HEPES, pH7.4) for 45 min at the room temperature. Fluorescence changes were read using a Fusion-alpha HT microplate reader.cAMP Assay: A 384-well drug plate was prepared to contain test compounds, PGE2 and cAMP in 16 serial dilutions in triplicate, using a Biomek station. HEK-EBNA cells expressing a target PG receptor subtype (EP2 or EP4) were suspended in a stimulation buffer (HBSS, 0.1% BSA, 0.5 mM IBMX and 5 mM HEPES, pH 7.4) in a density of 104 cells/5 μl. The reaction was initiated by mixing 5 μL drug dilutions with 5 μl of HEK-EBNA cells in a well, carried out for 30 min at room temperature, and followed by the addition of 5 μl anti-cAMP acceptor beads in the control buffer with Tween-20 (25 mM NaCl, 0.03% Tween-20, 5 mM HEPES, pH7.4). After 30 min in the dark at room temperature, the mixtures were incubated with 15 μl biotinylated-cAMP/strpavidin donor beads in Lysis/Detection buffer (0.1% BSA, 0.3% Tween-20 and 5 mM HEPES, pH7.4) for 45 min at the room temperature. Fluorescence changes were read using a Fusion-alpha HT microplate reader.

cAMP Assay: A 384-well drug plate was prepared to contain test compounds, PGE2 and cAMP in 16 serial dilutions in triplicate, using a Biomek station. HEK-EBNA cells expressing a target PG receptor subtype (EP2 or EP4) were suspended in a stimulation buffer (HBSS, 0.1% BSA, 0.5 mM IBMX and 5 mM HEPES, pH 7.4) in a density of 104 cells/5 μl. The reaction was initiated by mixing 5 μL drug dilutions with 5 μl of HEK-EBNA cells in a well, carried out for 30 min at room temperature, and followed by the addition of 5 μl anti-cAMP acceptor beads in the control buffer with Tween-20 (25 mM NaCl, 0.03% Tween-20, 5 mM HEPES, pH7.4). After 30 min in the dark at room temperature, the mixtures were incubated with 15 μl biotinylated-cAMP/strpavidin donor beads in Lysis/Detection buffer (0.1% BSA, 0.3% Tween-20 and 5 mM HEPES, pH7.4) for 45 min at the room temperature. Fluorescence changes were read using a Fusion-alpha HT microplate reader.cAMP Assay: A 384-well drug plate was prepared to contain test compounds, PGE2 and cAMP in 16 serial dilutions in triplicate, using a Biomek station. HEK-EBNA cells expressing a target PG receptor subtype (EP2 or EP4) were suspended in a stimulation buffer (HBSS, 0.1% BSA, 0.5 mM IBMX and 5 mM HEPES, pH 7.4) in a density of 104 cells/5 μl. The reaction was initiated by mixing 5 μL drug dilutions with 5 μl of HEK-EBNA cells in a well, carried out for 30 min at room temperature, and followed by the addition of 5 μl anti-cAMP acceptor beads in the control buffer with Tween-20 (25 mM NaCl, 0.03% Tween-20, 5 mM HEPES, pH7.4). After 30 min in the dark at room temperature, the mixtures were incubated with 15 μl biotinylated-cAMP/strpavidin donor beads in Lysis/Detection buffer (0.1% BSA, 0.3% Tween-20 and 5 mM HEPES, pH7.4) for 45 min at the room temperature. Fluorescence changes were read using a Fusion-alpha HT microplate reader.

cAMP Assay: A 384-well drug plate was prepared to contain test compounds, PGE2 and cAMP in 16 serial dilutions in triplicate, using a Biomek station. HEK-EBNA cells expressing a target PG receptor subtype (EP2 or EP4) were suspended in a stimulation buffer (HBSS, 0.1% BSA, 0.5 mM IBMX and 5 mM HEPES, pH 7.4) in a density of 104 cells/5 μl. The reaction was initiated by mixing 5 μL drug dilutions with 5 μl of HEK-EBNA cells in a well, carried out for 30 min at room temperature, and followed by the addition of 5 μl anti-cAMP acceptor beads in the control buffer with Tween-20 (25 mM NaCl, 0.03% Tween-20, 5 mM HEPES, pH7.4). After 30 min in the dark at room temperature, the mixtures were incubated with 15 μl biotinylated-cAMP/strpavidin donor beads in Lysis/Detection buffer (0.1% BSA, 0.3% Tween-20 and 5 mM HEPES, pH7.4) for 45 min at the room temperature. Fluorescence changes were read using a Fusion-alpha HT microplate reader.cAMP Assay: A 384-well drug plate was prepared to contain test compounds, PGE2 and cAMP in 16 serial dilutions in triplicate, using a Biomek station. HEK-EBNA cells expressing a target PG receptor subtype (EP2 or EP4) were suspended in a stimulation buffer (HBSS, 0.1% BSA, 0.5 mM IBMX and 5 mM HEPES, pH 7.4) in a density of 104 cells/5 μl. The reaction was initiated by mixing 5 μL drug dilutions with 5 μl of HEK-EBNA cells in a well, carried out for 30 min at room temperature, and followed by the addition of 5 μl anti-cAMP acceptor beads in the control buffer with Tween-20 (25 mM NaCl, 0.03% Tween-20, 5 mM HEPES, pH7.4). After 30 min in the dark at room temperature, the mixtures were incubated with 15 μl biotinylated-cAMP/strpavidin donor beads in Lysis/Detection buffer (0.1% BSA, 0.3% Tween-20 and 5 mM HEPES, pH7.4) for 45 min at the room temperature. Fluorescence changes were read using a Fusion-alpha HT microplate reader.

cAMP Assay: 1. Seed cells on an EP2 or EP4 STEP plate at a density of 40,000-80,000 cells/well in 200 uL of reduced serum medium containing 0.5% FBS. Place the plate in a 37° C. incubator with 5% CO2 and incubate overnight. 2. After 16-18 hours of incubation, aspirate the culture media from each well. 3. Add 200 ul of culture medium containing 500 uM IBMX (an inhibitor of cAMP phosphodiesterase) and different concentration of test compounds to the assigned wells. For each test compound, at least 8 concentrations starting at highest 10 M and lowest 0.01 pM were tested. In addition each concentration had triplicates. A PGE2 curve (concentrations from lowest to highest, 0 pM, 0.384 pM, 1.92 pM, 9.6 pM, 48 pM, 240 pM, 1200 pM, and 6000 pM) was always run in parallel with test compounds. 4. Incubate the cells in a cell culture incubator for 30 minutes. 5. Centrifuge the plate at 1,000x rpm for 10 minutes. 6. Aspirate the supernatant.cAMP Assay: 1. Seed cells on an EP2 or EP4 STEP plate at a density of 40,000-80,000 cells/well in 200 uL of reduced serum medium containing 0.5% FBS. Place the plate in a 37° C. incubator with 5% CO2 and incubate overnight. 2. After 16-18 hours of incubation, aspirate the culture media from each well. 3. Add 200 ul of culture medium containing 500 uM IBMX (an inhibitor of cAMP phosphodiesterase) and different concentration of test compounds to the assigned wells. For each test compound, at least 8 concentrations starting at highest 10 M and lowest 0.01 pM were tested. In addition each concentration had triplicates. A PGE2 curve (concentrations from lowest to highest, 0 pM, 0.384 pM, 1.92 pM, 9.6 pM, 48 pM, 240 pM, 1200 pM, and 6000 pM) was always run in parallel with test compounds. 4. Incubate the cells in a cell culture incubator for 30 minutes. 5. Centrifuge the plate at 1,000x rpm for 10 minutes. 6. Aspirate the supernatant.

cAMP Assay: 1. Seed cells on an EP2 or EP4 STEP plate at a density of 40,000-80,000 cells/well in 200 uL of reduced serum medium containing 0.5% FBS. Place the plate in a 37° C. incubator with 5% CO2 and incubate overnight. 2. After 16-18 hours of incubation, aspirate the culture media from each well. 3. Add 200 ul of culture medium containing 500 uM IBMX (an inhibitor of cAMP phosphodiesterase) and different concentration of test compounds to the assigned wells. For each test compound, at least 8 concentrations starting at highest 10 M and lowest 0.01 pM were tested. In addition each concentration had triplicates. A PGE2 curve (concentrations from lowest to highest, 0 pM, 0.384 pM, 1.92 pM, 9.6 pM, 48 pM, 240 pM, 1200 pM, and 6000 pM) was always run in parallel with test compounds. 4. Incubate the cells in a cell culture incubator for 30 minutes. 5. Centrifuge the plate at 1,000x rpm for 10 minutes. 6. Aspirate the supernatant.cAMP Assay: 1. Seed cells on an EP2 or EP4 STEP plate at a density of 40,000-80,000 cells/well in 200 uL of reduced serum medium containing 0.5% FBS. Place the plate in a 37° C. incubator with 5% CO2 and incubate overnight. 2. After 16-18 hours of incubation, aspirate the culture media from each well. 3. Add 200 ul of culture medium containing 500 uM IBMX (an inhibitor of cAMP phosphodiesterase) and different concentration of test compounds to the assigned wells. For each test compound, at least 8 concentrations starting at highest 10 M and lowest 0.01 pM were tested. In addition each concentration had triplicates. A PGE2 curve (concentrations from lowest to highest, 0 pM, 0.384 pM, 1.92 pM, 9.6 pM, 48 pM, 240 pM, 1200 pM, and 6000 pM) was always run in parallel with test compounds. 4. Incubate the cells in a cell culture incubator for 30 minutes. 5. Centrifuge the plate at 1,000x rpm for 10 minutes. 6. Aspirate the supernatant.

Agonist activity at human EP4 receptor by cAMP assayAgonist activity at human EP4 receptor by cAMP assay

Radioligand Binding: HEK-293 cells stably expressing the human or feline FP receptor, or EP1, EP2, EP3, or EP4 receptors were washed with TME buffer, scraped from the bottom of the flasks, and homogenized for 30 sec using a Brinkman PT 10/35 polytron. TME buffer was added to achieve a final 40 ml volume in the centrifuge tubes (the composition of TME is 100 mM TRIS base, 20 mM MgCl2, 2M EDTA; 10 N HCl is added to achieve a pH of 7.4).The cell homogenate was centrifuged at 19000 r.p.m. for 20 min at 4 C. using a Beckman Ti-60 rotor. The resultant pellet was resuspended in TME buffer to give a final 1 mg/ml protein concentration, as determined by Biorad assay. Radioligand binding competition assays vs. [3H-]17-phenyl PGF2 (5 nM) were performed in a 100 ul volume for 60 min. Binding reactions were started by adding plasma membrane fraction. The reaction was terminated by the addition of 4 ml ice-cold TRIS-HCl buffer and rapid filtration through glass fiber GF/B filters using a Brandel cell.Radioligand Binding: HEK-293 cells stably expressing the human or feline FP receptor, or EP1, EP2, EP3, or EP4 receptors were washed with TME buffer, scraped from the bottom of the flasks, and homogenized for 30 sec using a Brinkman PT 10/35 polytron. TME buffer was added to achieve a final 40 ml volume in the centrifuge tubes (the composition of TME is 100 mM TRIS base, 20 mM MgCl2, 2M EDTA; 10 N HCl is added to achieve a pH of 7.4).The cell homogenate was centrifuged at 19000 r.p.m. for 20 min at 4 C. using a Beckman Ti-60 rotor. The resultant pellet was resuspended in TME buffer to give a final 1 mg/ml protein concentration, as determined by Biorad assay. Radioligand binding competition assays vs. [3H-]17-phenyl PGF2 (5 nM) were performed in a 100 ul volume for 60 min. Binding reactions were started by adding plasma membrane fraction. The reaction was terminated by the addition of 4 ml ice-cold TRIS-HCl buffer and rapid filtration through glass fiber GF/B filters using a Brandel cell.

Radioligand Binding: HEK-293 cells stably expressing the human or feline FP receptor, or EP1, EP2, EP3, or EP4 receptors were washed with TME buffer, scraped from the bottom of the flasks, and homogenized for 30 sec using a Brinkman PT 10/35 polytron. TME buffer was added to achieve a final 40 ml volume in the centrifuge tubes (the composition of TME is 100 mM TRIS base, 20 mM MgCl2, 2M EDTA; 10 N HCl is added to achieve a pH of 7.4).The cell homogenate was centrifuged at 19000 r.p.m. for 20 min at 4 C. using a Beckman Ti-60 rotor. The resultant pellet was resuspended in TME buffer to give a final 1 mg/ml protein concentration, as determined by Biorad assay. Radioligand binding competition assays vs. [3H-]17-phenyl PGF2 (5 nM) were performed in a 100 ul volume for 60 min. Binding reactions were started by adding plasma membrane fraction. The reaction was terminated by the addition of 4 ml ice-cold TRIS-HCl buffer and rapid filtration through glass fiber GF/B filters using a Brandel cell.Radioligand Binding: HEK-293 cells stably expressing the human or feline FP receptor, or EP1, EP2, EP3, or EP4 receptors were washed with TME buffer, scraped from the bottom of the flasks, and homogenized for 30 sec using a Brinkman PT 10/35 polytron. TME buffer was added to achieve a final 40 ml volume in the centrifuge tubes (the composition of TME is 100 mM TRIS base, 20 mM MgCl2, 2M EDTA; 10 N HCl is added to achieve a pH of 7.4).The cell homogenate was centrifuged at 19000 r.p.m. for 20 min at 4 C. using a Beckman Ti-60 rotor. The resultant pellet was resuspended in TME buffer to give a final 1 mg/ml protein concentration, as determined by Biorad assay. Radioligand binding competition assays vs. [3H-]17-phenyl PGF2 (5 nM) were performed in a 100 ul volume for 60 min. Binding reactions were started by adding plasma membrane fraction. The reaction was terminated by the addition of 4 ml ice-cold TRIS-HCl buffer and rapid filtration through glass fiber GF/B filters using a Brandel cell.

cAMP Assay: A 384-well drug plate was prepared to contain test compounds, PGE2 and cAMP in 16 serial dilutions in triplicate, using a Biomek station. HEK-EBNA cells expressing a target PG receptor subtype (EP2 or EP4) were suspended in a stimulation buffer (HBSS, 0.1% BSA, 0.5 mM IBMX and 5 mM HEPES, pH 7.4) in a density of 104 cells/5 μl. The reaction was initiated by mixing 5 μL drug dilutions with 5 μl of HEK-EBNA cells in a well, carried out for 30 min at room temperature, and followed by the addition of 5 μl anti-cAMP acceptor beads in the control buffer with Tween-20 (25 mM NaCl, 0.03% Tween-20, 5 mM HEPES, pH7.4). After 30 min in the dark at room temperature, the mixtures were incubated with 15 μl biotinylated-cAMP/strpavidin donor beads in Lysis/Detection buffer (0.1% BSA, 0.3% Tween-20 and 5 mM HEPES, pH7.4) for 45 min at the room temperature. Fluorescence changes were read using a Fusion-alpha HT microplate reader.cAMP Assay: A 384-well drug plate was prepared to contain test compounds, PGE2 and cAMP in 16 serial dilutions in triplicate, using a Biomek station. HEK-EBNA cells expressing a target PG receptor subtype (EP2 or EP4) were suspended in a stimulation buffer (HBSS, 0.1% BSA, 0.5 mM IBMX and 5 mM HEPES, pH 7.4) in a density of 104 cells/5 μl. The reaction was initiated by mixing 5 μL drug dilutions with 5 μl of HEK-EBNA cells in a well, carried out for 30 min at room temperature, and followed by the addition of 5 μl anti-cAMP acceptor beads in the control buffer with Tween-20 (25 mM NaCl, 0.03% Tween-20, 5 mM HEPES, pH7.4). After 30 min in the dark at room temperature, the mixtures were incubated with 15 μl biotinylated-cAMP/strpavidin donor beads in Lysis/Detection buffer (0.1% BSA, 0.3% Tween-20 and 5 mM HEPES, pH7.4) for 45 min at the room temperature. Fluorescence changes were read using a Fusion-alpha HT microplate reader.

cAMP Assay: A 384-well drug plate was prepared to contain test compounds, PGE2 and cAMP in 16 serial dilutions in triplicate, using a Biomek station. HEK-EBNA cells expressing a target PG receptor subtype (EP2 or EP4) were suspended in a stimulation buffer (HBSS, 0.1% BSA, 0.5 mM IBMX and 5 mM HEPES, pH 7.4) in a density of 104 cells/5 μl. The reaction was initiated by mixing 5 μL drug dilutions with 5 μl of HEK-EBNA cells in a well, carried out for 30 min at room temperature, and followed by the addition of 5 μl anti-cAMP acceptor beads in the control buffer with Tween-20 (25 mM NaCl, 0.03% Tween-20, 5 mM HEPES, pH7.4). After 30 min in the dark at room temperature, the mixtures were incubated with 15 μl biotinylated-cAMP/strpavidin donor beads in Lysis/Detection buffer (0.1% BSA, 0.3% Tween-20 and 5 mM HEPES, pH7.4) for 45 min at the room temperature. Fluorescence changes were read using a Fusion-alpha HT microplate reader.cAMP Assay: A 384-well drug plate was prepared to contain test compounds, PGE2 and cAMP in 16 serial dilutions in triplicate, using a Biomek station. HEK-EBNA cells expressing a target PG receptor subtype (EP2 or EP4) were suspended in a stimulation buffer (HBSS, 0.1% BSA, 0.5 mM IBMX and 5 mM HEPES, pH 7.4) in a density of 104 cells/5 μl. The reaction was initiated by mixing 5 μL drug dilutions with 5 μl of HEK-EBNA cells in a well, carried out for 30 min at room temperature, and followed by the addition of 5 μl anti-cAMP acceptor beads in the control buffer with Tween-20 (25 mM NaCl, 0.03% Tween-20, 5 mM HEPES, pH7.4). After 30 min in the dark at room temperature, the mixtures were incubated with 15 μl biotinylated-cAMP/strpavidin donor beads in Lysis/Detection buffer (0.1% BSA, 0.3% Tween-20 and 5 mM HEPES, pH7.4) for 45 min at the room temperature. Fluorescence changes were read using a Fusion-alpha HT microplate reader.

Agonist activity at human EP4 receptor expressed in HEK293T/17 cells assessed as increase in intracellular cAMP level incubated for 30 mins by ELISAAgonist activity at human EP4 receptor expressed in HEK293T/17 cells assessed as increase in intracellular cAMP level incubated for 30 mins by ELISA

Agonist activity at human prostanoid EP4 receptor expressed in HEK293 cells assessed as potentiation of PGE2-induced cAMP accumulation by scintillation proximity assayAgonist activity at human prostanoid EP4 receptor expressed in HEK293 cells assessed as potentiation of PGE2-induced cAMP accumulation by scintillation proximity assay

cAMP Assay: 1. Seed cells on an EP2 or EP4 STEP plate at a density of 40,000-80,000 cells/well in 200 uL of reduced serum medium containing 0.5% FBS. Place the plate in a 37° C. incubator with 5% CO2 and incubate overnight. 2. After 16-18 hours of incubation, aspirate the culture media from each well. 3. Add 200 ul of culture medium containing 500 uM IBMX (an inhibitor of cAMP phosphodiesterase) and different concentration of test compounds to the assigned wells. For each test compound, at least 8 concentrations starting at highest 10 M and lowest 0.01 pM were tested. In addition each concentration had triplicates. A PGE2 curve (concentrations from lowest to highest, 0 pM, 0.384 pM, 1.92 pM, 9.6 pM, 48 pM, 240 pM, 1200 pM, and 6000 pM) was always run in parallel with test compounds. 4. Incubate the cells in a cell culture incubator for 30 minutes. 5. Centrifuge the plate at 1,000x rpm for 10 minutes. 6. Aspirate the supernatant.cAMP Assay: 1. Seed cells on an EP2 or EP4 STEP plate at a density of 40,000-80,000 cells/well in 200 uL of reduced serum medium containing 0.5% FBS. Place the plate in a 37° C. incubator with 5% CO2 and incubate overnight. 2. After 16-18 hours of incubation, aspirate the culture media from each well. 3. Add 200 ul of culture medium containing 500 uM IBMX (an inhibitor of cAMP phosphodiesterase) and different concentration of test compounds to the assigned wells. For each test compound, at least 8 concentrations starting at highest 10 M and lowest 0.01 pM were tested. In addition each concentration had triplicates. A PGE2 curve (concentrations from lowest to highest, 0 pM, 0.384 pM, 1.92 pM, 9.6 pM, 48 pM, 240 pM, 1200 pM, and 6000 pM) was always run in parallel with test compounds. 4. Incubate the cells in a cell culture incubator for 30 minutes. 5. Centrifuge the plate at 1,000x rpm for 10 minutes. 6. Aspirate the supernatant.

cAMP Assay: 1. Seed cells on an EP2 or EP4 STEP plate at a density of 40,000-80,000 cells/well in 200 uL of reduced serum medium containing 0.5% FBS. Place the plate in a 37° C. incubator with 5% CO2 and incubate overnight. 2. After 16-18 hours of incubation, aspirate the culture media from each well. 3. Add 200 ul of culture medium containing 500 uM IBMX (an inhibitor of cAMP phosphodiesterase) and different concentration of test compounds to the assigned wells. For each test compound, at least 8 concentrations starting at highest 10 M and lowest 0.01 pM were tested. In addition each concentration had triplicates. A PGE2 curve (concentrations from lowest to highest, 0 pM, 0.384 pM, 1.92 pM, 9.6 pM, 48 pM, 240 pM, 1200 pM, and 6000 pM) was always run in parallel with test compounds. 4. Incubate the cells in a cell culture incubator for 30 minutes. 5. Centrifuge the plate at 1,000x rpm for 10 minutes. 6. Aspirate the supernatant.cAMP Assay: 1. Seed cells on an EP2 or EP4 STEP plate at a density of 40,000-80,000 cells/well in 200 uL of reduced serum medium containing 0.5% FBS. Place the plate in a 37° C. incubator with 5% CO2 and incubate overnight. 2. After 16-18 hours of incubation, aspirate the culture media from each well. 3. Add 200 ul of culture medium containing 500 uM IBMX (an inhibitor of cAMP phosphodiesterase) and different concentration of test compounds to the assigned wells. For each test compound, at least 8 concentrations starting at highest 10 M and lowest 0.01 pM were tested. In addition each concentration had triplicates. A PGE2 curve (concentrations from lowest to highest, 0 pM, 0.384 pM, 1.92 pM, 9.6 pM, 48 pM, 240 pM, 1200 pM, and 6000 pM) was always run in parallel with test compounds. 4. Incubate the cells in a cell culture incubator for 30 minutes. 5. Centrifuge the plate at 1,000x rpm for 10 minutes. 6. Aspirate the supernatant.

Radioligand Binding: HEK-293 cells stably expressing the human or feline FP receptor, or EP1, EP2, EP3, or EP4 receptors were washed with TME buffer, scraped from the bottom of the flasks, and homogenized for 30 sec using a Brinkman PT 10/35 polytron. TME buffer was added to achieve a final 40 ml volume in the centrifuge tubes (the composition of TME is 100 mM TRIS base, 20 mM MgCl2, 2M EDTA; 10 N HCl is added to achieve a pH of 7.4).The cell homogenate was centrifuged at 19000 r.p.m. for 20 min at 4 C. using a Beckman Ti-60 rotor. The resultant pellet was resuspended in TME buffer to give a final 1 mg/ml protein concentration, as determined by Biorad assay. Radioligand binding competition assays vs. [3H-]17-phenyl PGF2 (5 nM) were performed in a 100 ul volume for 60 min. Binding reactions were started by adding plasma membrane fraction. The reaction was terminated by the addition of 4 ml ice-cold TRIS-HCl buffer and rapid filtration through glass fiber GF/B filters using a Brandel cell.Radioligand Binding: HEK-293 cells stably expressing the human or feline FP receptor, or EP1, EP2, EP3, or EP4 receptors were washed with TME buffer, scraped from the bottom of the flasks, and homogenized for 30 sec using a Brinkman PT 10/35 polytron. TME buffer was added to achieve a final 40 ml volume in the centrifuge tubes (the composition of TME is 100 mM TRIS base, 20 mM MgCl2, 2M EDTA; 10 N HCl is added to achieve a pH of 7.4).The cell homogenate was centrifuged at 19000 r.p.m. for 20 min at 4 C. using a Beckman Ti-60 rotor. The resultant pellet was resuspended in TME buffer to give a final 1 mg/ml protein concentration, as determined by Biorad assay. Radioligand binding competition assays vs. [3H-]17-phenyl PGF2 (5 nM) were performed in a 100 ul volume for 60 min. Binding reactions were started by adding plasma membrane fraction. The reaction was terminated by the addition of 4 ml ice-cold TRIS-HCl buffer and rapid filtration through glass fiber GF/B filters using a Brandel cell.

Agonist activity at human EP4 receptor expressed in HEK293T/17 cells assessed as increase in GalphaS-mediated CREB activation measured after 6 to 24 hrs by SEAP reporter gene-based chemiluminescence assayAgonist activity at human EP4 receptor expressed in HEK293T/17 cells assessed as increase in GalphaS-mediated CREB activation measured after 6 to 24 hrs by SEAP reporter gene-based chemiluminescence assay

cAMP Assay: 1. Seed cells on an EP2 or EP4 STEP plate at a density of 40,000-80,000 cells/well in 200 uL of reduced serum medium containing 0.5% FBS. Place the plate in a 37° C. incubator with 5% CO2 and incubate overnight. 2. After 16-18 hours of incubation, aspirate the culture media from each well. 3. Add 200 ul of culture medium containing 500 uM IBMX (an inhibitor of cAMP phosphodiesterase) and different concentration of test compounds to the assigned wells. For each test compound, at least 8 concentrations starting at highest 10 M and lowest 0.01 pM were tested. In addition each concentration had triplicates. A PGE2 curve (concentrations from lowest to highest, 0 pM, 0.384 pM, 1.92 pM, 9.6 pM, 48 pM, 240 pM, 1200 pM, and 6000 pM) was always run in parallel with test compounds. 4. Incubate the cells in a cell culture incubator for 30 minutes. 5. Centrifuge the plate at 1,000x rpm for 10 minutes. 6. Aspirate the supernatant.cAMP Assay: 1. Seed cells on an EP2 or EP4 STEP plate at a density of 40,000-80,000 cells/well in 200 uL of reduced serum medium containing 0.5% FBS. Place the plate in a 37° C. incubator with 5% CO2 and incubate overnight. 2. After 16-18 hours of incubation, aspirate the culture media from each well. 3. Add 200 ul of culture medium containing 500 uM IBMX (an inhibitor of cAMP phosphodiesterase) and different concentration of test compounds to the assigned wells. For each test compound, at least 8 concentrations starting at highest 10 M and lowest 0.01 pM were tested. In addition each concentration had triplicates. A PGE2 curve (concentrations from lowest to highest, 0 pM, 0.384 pM, 1.92 pM, 9.6 pM, 48 pM, 240 pM, 1200 pM, and 6000 pM) was always run in parallel with test compounds. 4. Incubate the cells in a cell culture incubator for 30 minutes. 5. Centrifuge the plate at 1,000x rpm for 10 minutes. 6. Aspirate the supernatant.

Activity at rat EP4 transfected in HEK293 cells by cAMP accumulationActivity at rat EP4 transfected in HEK293 cells by cAMP accumulation

Agonist activity at EP4 receptor expressed in HEK293 cells assessed as cAMP accumulationAgonist activity at EP4 receptor expressed in HEK293 cells assessed as cAMP accumulation

Agonist activity at human EP4 receptor expressed in CHO cells assessed as increase in intracellular cAMP level after 30 mins by HTRF methodAgonist activity at human EP4 receptor expressed in CHO cells assessed as increase in intracellular cAMP level after 30 mins by HTRF method

Agonist activity at rat EP4 receptor expressed in HEK293 cells assessed as cAMP activationAgonist activity at rat EP4 receptor expressed in HEK293 cells assessed as cAMP activation

cAMP Assay: A 384-well drug plate was prepared to contain test compounds, PGE2 and cAMP in 16 serial dilutions in triplicate, using a Biomek station. HEK-EBNA cells expressing a target PG receptor subtype (EP2 or EP4) were suspended in a stimulation buffer (HBSS, 0.1% BSA, 0.5 mM IBMX and 5 mM HEPES, pH 7.4) in a density of 104 cells/5 μl. The reaction was initiated by mixing 5 μL drug dilutions with 5 μl of HEK-EBNA cells in a well, carried out for 30 min at room temperature, and followed by the addition of 5 μl anti-cAMP acceptor beads in the control buffer with Tween-20 (25 mM NaCl, 0.03% Tween-20, 5 mM HEPES, pH7.4). After 30 min in the dark at room temperature, the mixtures were incubated with 15 μl biotinylated-cAMP/strpavidin donor beads in Lysis/Detection buffer (0.1% BSA, 0.3% Tween-20 and 5 mM HEPES, pH7.4) for 45 min at the room temperature. Fluorescence changes were read using a Fusion-alpha HT microplate reader.cAMP Assay: A 384-well drug plate was prepared to contain test compounds, PGE2 and cAMP in 16 serial dilutions in triplicate, using a Biomek station. HEK-EBNA cells expressing a target PG receptor subtype (EP2 or EP4) were suspended in a stimulation buffer (HBSS, 0.1% BSA, 0.5 mM IBMX and 5 mM HEPES, pH 7.4) in a density of 104 cells/5 μl. The reaction was initiated by mixing 5 μL drug dilutions with 5 μl of HEK-EBNA cells in a well, carried out for 30 min at room temperature, and followed by the addition of 5 μl anti-cAMP acceptor beads in the control buffer with Tween-20 (25 mM NaCl, 0.03% Tween-20, 5 mM HEPES, pH7.4). After 30 min in the dark at room temperature, the mixtures were incubated with 15 μl biotinylated-cAMP/strpavidin donor beads in Lysis/Detection buffer (0.1% BSA, 0.3% Tween-20 and 5 mM HEPES, pH7.4) for 45 min at the room temperature. Fluorescence changes were read using a Fusion-alpha HT microplate reader.

Agonist activity at human EP4 receptor expressed in HEK293T/17 cells assessed as increase in intracellular cAMP level incubated for 30 mins by ELISAAgonist activity at human EP4 receptor expressed in HEK293T/17 cells assessed as increase in intracellular cAMP level incubated for 30 mins by ELISA

Activity at rat EP4 transfected in HEK293 cells by cAMP accumulationActivity at rat EP4 transfected in HEK293 cells by cAMP accumulation

Agonist activity at rat EP4 receptor expressed in CHO cells assessed as cAMP production after 10 mins by radioimmunoassayAgonist activity at rat EP4 receptor expressed in CHO cells assessed as cAMP production after 10 mins by radioimmunoassay

cAMP Assay: 1. Seed cells on an EP2 or EP4 STEP plate at a density of 40,000-80,000 cells/well in 200 uL of reduced serum medium containing 0.5% FBS. Place the plate in a 37° C. incubator with 5% CO2 and incubate overnight. 2. After 16-18 hours of incubation, aspirate the culture media from each well. 3. Add 200 ul of culture medium containing 500 uM IBMX (an inhibitor of cAMP phosphodiesterase) and different concentration of test compounds to the assigned wells. For each test compound, at least 8 concentrations starting at highest 10 M and lowest 0.01 pM were tested. In addition each concentration had triplicates. A PGE2 curve (concentrations from lowest to highest, 0 pM, 0.384 pM, 1.92 pM, 9.6 pM, 48 pM, 240 pM, 1200 pM, and 6000 pM) was always run in parallel with test compounds. 4. Incubate the cells in a cell culture incubator for 30 minutes. 5. Centrifuge the plate at 1,000x rpm for 10 minutes. 6. Aspirate the supernatant.cAMP Assay: 1. Seed cells on an EP2 or EP4 STEP plate at a density of 40,000-80,000 cells/well in 200 uL of reduced serum medium containing 0.5% FBS. Place the plate in a 37° C. incubator with 5% CO2 and incubate overnight. 2. After 16-18 hours of incubation, aspirate the culture media from each well. 3. Add 200 ul of culture medium containing 500 uM IBMX (an inhibitor of cAMP phosphodiesterase) and different concentration of test compounds to the assigned wells. For each test compound, at least 8 concentrations starting at highest 10 M and lowest 0.01 pM were tested. In addition each concentration had triplicates. A PGE2 curve (concentrations from lowest to highest, 0 pM, 0.384 pM, 1.92 pM, 9.6 pM, 48 pM, 240 pM, 1200 pM, and 6000 pM) was always run in parallel with test compounds. 4. Incubate the cells in a cell culture incubator for 30 minutes. 5. Centrifuge the plate at 1,000x rpm for 10 minutes. 6. Aspirate the supernatant.

Agonist activity against rat EP4 receptor expressed in HEK293 cells assessed as stimulation of cAMP releaseAgonist activity against rat EP4 receptor expressed in HEK293 cells assessed as stimulation of cAMP release

cAMP Assay: 1. Seed cells on an EP2 or EP4 STEP plate at a density of 40,000-80,000 cells/well in 200 uL of reduced serum medium containing 0.5% FBS. Place the plate in a 37° C. incubator with 5% CO2 and incubate overnight. 2. After 16-18 hours of incubation, aspirate the culture media from each well. 3. Add 200 ul of culture medium containing 500 uM IBMX (an inhibitor of cAMP phosphodiesterase) and different concentration of test compounds to the assigned wells. For each test compound, at least 8 concentrations starting at highest 10 M and lowest 0.01 pM were tested. In addition each concentration had triplicates. A PGE2 curve (concentrations from lowest to highest, 0 pM, 0.384 pM, 1.92 pM, 9.6 pM, 48 pM, 240 pM, 1200 pM, and 6000 pM) was always run in parallel with test compounds. 4. Incubate the cells in a cell culture incubator for 30 minutes. 5. Centrifuge the plate at 1,000x rpm for 10 minutes. 6. Aspirate the supernatant.cAMP Assay: 1. Seed cells on an EP2 or EP4 STEP plate at a density of 40,000-80,000 cells/well in 200 uL of reduced serum medium containing 0.5% FBS. Place the plate in a 37° C. incubator with 5% CO2 and incubate overnight. 2. After 16-18 hours of incubation, aspirate the culture media from each well. 3. Add 200 ul of culture medium containing 500 uM IBMX (an inhibitor of cAMP phosphodiesterase) and different concentration of test compounds to the assigned wells. For each test compound, at least 8 concentrations starting at highest 10 M and lowest 0.01 pM were tested. In addition each concentration had triplicates. A PGE2 curve (concentrations from lowest to highest, 0 pM, 0.384 pM, 1.92 pM, 9.6 pM, 48 pM, 240 pM, 1200 pM, and 6000 pM) was always run in parallel with test compounds. 4. Incubate the cells in a cell culture incubator for 30 minutes. 5. Centrifuge the plate at 1,000x rpm for 10 minutes. 6. Aspirate the supernatant.

Agonist activity at rat EP4 receptorAgonist activity at rat EP4 receptor

Agonist activity at rat EP4 receptor expressed in CHO cells assessed as cAMP production after 10 mins by radioimmunoassayAgonist activity at rat EP4 receptor expressed in CHO cells assessed as cAMP production after 10 mins by radioimmunoassay

Agonist activity against recombinant prostanoid EP4 receptor stably transfected in CHO cellsAgonist activity against recombinant prostanoid EP4 receptor stably transfected in CHO cells

Agonist activity at human prostanoid EP4 receptor expressed in HEK293 cells assessed as potentiation of PGE2-induced cAMP accumulation by scintillation proximity assayAgonist activity at human prostanoid EP4 receptor expressed in HEK293 cells assessed as potentiation of PGE2-induced cAMP accumulation by scintillation proximity assay

cAMP Assay: A 384-well drug plate was prepared to contain test compounds, PGE2 and cAMP in 16 serial dilutions in triplicate, using a Biomek station. HEK-EBNA cells expressing a target PG receptor subtype (EP2 or EP4) were suspended in a stimulation buffer (HBSS, 0.1% BSA, 0.5 mM IBMX and 5 mM HEPES, pH 7.4) in a density of 104 cells/5 μl. The reaction was initiated by mixing 5 μL drug dilutions with 5 μl of HEK-EBNA cells in a well, carried out for 30 min at room temperature, and followed by the addition of 5 μl anti-cAMP acceptor beads in the control buffer with Tween-20 (25 mM NaCl, 0.03% Tween-20, 5 mM HEPES, pH7.4). After 30 min in the dark at room temperature, the mixtures were incubated with 15 μl biotinylated-cAMP/strpavidin donor beads in Lysis/Detection buffer (0.1% BSA, 0.3% Tween-20 and 5 mM HEPES, pH7.4) for 45 min at the room temperature. Fluorescence changes were read using a Fusion-alpha HT microplate reader.cAMP Assay: A 384-well drug plate was prepared to contain test compounds, PGE2 and cAMP in 16 serial dilutions in triplicate, using a Biomek station. HEK-EBNA cells expressing a target PG receptor subtype (EP2 or EP4) were suspended in a stimulation buffer (HBSS, 0.1% BSA, 0.5 mM IBMX and 5 mM HEPES, pH 7.4) in a density of 104 cells/5 μl. The reaction was initiated by mixing 5 μL drug dilutions with 5 μl of HEK-EBNA cells in a well, carried out for 30 min at room temperature, and followed by the addition of 5 μl anti-cAMP acceptor beads in the control buffer with Tween-20 (25 mM NaCl, 0.03% Tween-20, 5 mM HEPES, pH7.4). After 30 min in the dark at room temperature, the mixtures were incubated with 15 μl biotinylated-cAMP/strpavidin donor beads in Lysis/Detection buffer (0.1% BSA, 0.3% Tween-20 and 5 mM HEPES, pH7.4) for 45 min at the room temperature. Fluorescence changes were read using a Fusion-alpha HT microplate reader.

cAMP Assay: A 384-well drug plate was prepared to contain test compounds, PGE2 and cAMP in 16 serial dilutions in triplicate, using a Biomek station. HEK-EBNA cells expressing a target PG receptor subtype (EP2 or EP4) were suspended in a stimulation buffer (HBSS, 0.1% BSA, 0.5 mM IBMX and 5 mM HEPES, pH 7.4) in a density of 104 cells/5 μl. The reaction was initiated by mixing 5 μL drug dilutions with 5 μl of HEK-EBNA cells in a well, carried out for 30 min at room temperature, and followed by the addition of 5 μl anti-cAMP acceptor beads in the control buffer with Tween-20 (25 mM NaCl, 0.03% Tween-20, 5 mM HEPES, pH7.4). After 30 min in the dark at room temperature, the mixtures were incubated with 15 μl biotinylated-cAMP/strpavidin donor beads in Lysis/Detection buffer (0.1% BSA, 0.3% Tween-20 and 5 mM HEPES, pH7.4) for 45 min at the room temperature. Fluorescence changes were read using a Fusion-alpha HT microplate reader.cAMP Assay: A 384-well drug plate was prepared to contain test compounds, PGE2 and cAMP in 16 serial dilutions in triplicate, using a Biomek station. HEK-EBNA cells expressing a target PG receptor subtype (EP2 or EP4) were suspended in a stimulation buffer (HBSS, 0.1% BSA, 0.5 mM IBMX and 5 mM HEPES, pH 7.4) in a density of 104 cells/5 μl. The reaction was initiated by mixing 5 μL drug dilutions with 5 μl of HEK-EBNA cells in a well, carried out for 30 min at room temperature, and followed by the addition of 5 μl anti-cAMP acceptor beads in the control buffer with Tween-20 (25 mM NaCl, 0.03% Tween-20, 5 mM HEPES, pH7.4). After 30 min in the dark at room temperature, the mixtures were incubated with 15 μl biotinylated-cAMP/strpavidin donor beads in Lysis/Detection buffer (0.1% BSA, 0.3% Tween-20 and 5 mM HEPES, pH7.4) for 45 min at the room temperature. Fluorescence changes were read using a Fusion-alpha HT microplate reader.

cAMP Assay: EP4 receptors couple to Gs and mediate elevations in cAMP concentration, although they do participate in other pathways as well. There are some redundancies in function between EP2 and EP4 receptors. For example, both receptors induce PGE2-mediated RANKL through cAMP.cAMP Assay: EP4 receptors couple to Gs and mediate elevations in cAMP concentration, although they do participate in other pathways as well. There are some redundancies in function between EP2 and EP4 receptors. For example, both receptors induce PGE2-mediated RANKL through cAMP.

Agonist activity at rat EP4 receptor expressed in CHO cells assessed as cAMP production after 10 mins by radioimmunoassayAgonist activity at rat EP4 receptor expressed in CHO cells assessed as cAMP production after 10 mins by radioimmunoassay

cAMP Assay: 1. Seed cells on an EP2 or EP4 STEP plate at a density of 40,000-80,000 cells/well in 200 uL of reduced serum medium containing 0.5% FBS. Place the plate in a 37° C. incubator with 5% CO2 and incubate overnight. 2. After 16-18 hours of incubation, aspirate the culture media from each well. 3. Add 200 ul of culture medium containing 500 uM IBMX (an inhibitor of cAMP phosphodiesterase) and different concentration of test compounds to the assigned wells. For each test compound, at least 8 concentrations starting at highest 10 M and lowest 0.01 pM were tested. In addition each concentration had triplicates. A PGE2 curve (concentrations from lowest to highest, 0 pM, 0.384 pM, 1.92 pM, 9.6 pM, 48 pM, 240 pM, 1200 pM, and 6000 pM) was always run in parallel with test compounds. 4. Incubate the cells in a cell culture incubator for 30 minutes. 5. Centrifuge the plate at 1,000x rpm for 10 minutes. 6. Aspirate the supernatant.cAMP Assay: 1. Seed cells on an EP2 or EP4 STEP plate at a density of 40,000-80,000 cells/well in 200 uL of reduced serum medium containing 0.5% FBS. Place the plate in a 37° C. incubator with 5% CO2 and incubate overnight. 2. After 16-18 hours of incubation, aspirate the culture media from each well. 3. Add 200 ul of culture medium containing 500 uM IBMX (an inhibitor of cAMP phosphodiesterase) and different concentration of test compounds to the assigned wells. For each test compound, at least 8 concentrations starting at highest 10 M and lowest 0.01 pM were tested. In addition each concentration had triplicates. A PGE2 curve (concentrations from lowest to highest, 0 pM, 0.384 pM, 1.92 pM, 9.6 pM, 48 pM, 240 pM, 1200 pM, and 6000 pM) was always run in parallel with test compounds. 4. Incubate the cells in a cell culture incubator for 30 minutes. 5. Centrifuge the plate at 1,000x rpm for 10 minutes. 6. Aspirate the supernatant.

Agonist activity at rat EP4 receptor expressed in CHO cells assessed as cAMP production after 10 mins by radioimmunoassayAgonist activity at rat EP4 receptor expressed in CHO cells assessed as cAMP production after 10 mins by radioimmunoassay

Agonist activity at rat EP4 receptor expressed in CHO cells assessed as cAMP production after 10 mins by radioimmunoassayAgonist activity at rat EP4 receptor expressed in CHO cells assessed as cAMP production after 10 mins by radioimmunoassay

Agonist activity at mouse EP4 receptor expressed in CHO cells assessed as cAMP productionAgonist activity at mouse EP4 receptor expressed in CHO cells assessed as cAMP production

Agonist activity at rat EP4 receptor expressed in CHO cells assessed as cAMP production after 10 mins by radioimmunoassayAgonist activity at rat EP4 receptor expressed in CHO cells assessed as cAMP production after 10 mins by radioimmunoassay

Effective concentration for increased intracellular c-AMP production by mouse Prostanoid EP4 receptorEffective concentration for increased intracellular c-AMP production by mouse Prostanoid EP4 receptor

Activity at rat EP4 transfected in HEK293 cells by cAMP accumulationActivity at rat EP4 transfected in HEK293 cells by cAMP accumulation

Agonist activity at human EP4 receptor expressed in HEK293T/17 cells assessed as increase in intracellular cAMP level incubated for 30 mins by ELISAAgonist activity at human EP4 receptor expressed in HEK293T/17 cells assessed as increase in intracellular cAMP level incubated for 30 mins by ELISA

Agonist activity at rat EP4 receptor expressed in CHO cells assessed as cAMP production after 10 mins by radioimmunoassayAgonist activity at rat EP4 receptor expressed in CHO cells assessed as cAMP production after 10 mins by radioimmunoassay

Agonist activity at rat EP4 receptor expressed in CHO cells assessed as cAMP production after 10 mins by radioimmunoassayAgonist activity at rat EP4 receptor expressed in CHO cells assessed as cAMP production after 10 mins by radioimmunoassay

Cell Based Assay: Ca2+ signaling studies were performed using a FLIPR TETRA system (Molecular Devices, Sunnyvale, Calif., USA) in the 384-format. This is a high-throughput instrument for cell-based assays to monitor Ca2+ signaling associated with GPCRs and ion channels. Cells were seeded at a density of 5×104 cells/well in BioCoat poly-D-lysine coated, black wall, clear bottom 384-well plates (BD Biosciences, Franklin lakes, NJ, USA) and allowed to attach overnight in an incubator at 37° C. The cells were then washed twice with HBSS-HEPES buffer (Hanks' balanced salt solution without bicarbonate and phenol red, 20 mM HEPES, pH 7.4) using an ELx405 Select CW Microplate Washer (BioTek, Winooski, Vt., USA). After 60 min of dye-loading in the dark using the Ca2+-sensitive dye Fluo-4AM (Invitrogen, Carlsbad, Calif., USA), at a final concentration of 2×10^−6M, the plates were washed 4 times with HBSS-HEPES buffer to remove excess dye and leaving 50 μl of buffer in each well. The plates were then placed in the FLIPR TETRA instrument and allowed to equilibrate at 37° C. AGN-211377 was added in a 25 μl volume to each well to give final concentrations of 0.1 μM, 0.3 μM, 1 μM, 3 μM, 10 μM, and 30 μM; or 0.067 μM, 0.1 μM, 0.2 μM, 0.3 μM, 0.67 μM, and 1 μM for cells over-expressing TP receptors. After 4.5 minutes, a 7-point serial dilution of the standard agonist for the corresponding receptor, in a 25 μl volume was injected at the final concentrations from 10^−11M to 10^−5M in 10-fold serial dilution increments for cells expressing human recombinant DP1, EP1, EP2, EP3, EP4, FP, and IP receptors. The dose range for the standard agonist for human recombinant TP receptors was from 10^−12M to 10^−6M. HBSS-HEPES buffer was used as the negative control for the standard agonists. Cells were excited with LED (light emitting diode) excitation at 470-495 nm and emission was measured through an emission filter at 515-575 nm. Assay plates were read for 3.5 minutes using the FLIPRTETRA.Cell Based Assay: Ca2+ signaling studies were performed using a FLIPR TETRA system (Molecular Devices, Sunnyvale, Calif., USA) in the 384-format. This is a high-throughput instrument for cell-based assays to monitor Ca2+ signaling associated with GPCRs and ion channels. Cells were seeded at a density of 5×104 cells/well in BioCoat poly-D-lysine coated, black wall, clear bottom 384-well plates (BD Biosciences, Franklin lakes, NJ, USA) and allowed to attach overnight in an incubator at 37° C. The cells were then washed twice with HBSS-HEPES buffer (Hanks' balanced salt solution without bicarbonate and phenol red, 20 mM HEPES, pH 7.4) using an ELx405 Select CW Microplate Washer (BioTek, Winooski, Vt., USA). After 60 min of dye-loading in the dark using the Ca2+-sensitive dye Fluo-4AM (Invitrogen, Carlsbad, Calif., USA), at a final concentration of 2×10^−6M, the plates were washed 4 times with HBSS-HEPES buffer to remove excess dye and leaving 50 μl of buffer in each well. The plates were then placed in the FLIPR TETRA instrument and allowed to equilibrate at 37° C. AGN-211377 was added in a 25 μl volume to each well to give final concentrations of 0.1 μM, 0.3 μM, 1 μM, 3 μM, 10 μM, and 30 μM; or 0.067 μM, 0.1 μM, 0.2 μM, 0.3 μM, 0.67 μM, and 1 μM for cells over-expressing TP receptors. After 4.5 minutes, a 7-point serial dilution of the standard agonist for the corresponding receptor, in a 25 μl volume was injected at the final concentrations from 10^−11M to 10^−5M in 10-fold serial dilution increments for cells expressing human recombinant DP1, EP1, EP2, EP3, EP4, FP, and IP receptors. The dose range for the standard agonist for human recombinant TP receptors was from 10^−12M to 10^−6M. HBSS-HEPES buffer was used as the negative control for the standard agonists. Cells were excited with LED (light emitting diode) excitation at 470-495 nm and emission was measured through an emission filter at 515-575 nm. Assay plates were read for 3.5 minutes using the FLIPRTETRA.

Effective concentration which increases intracellular c-AMP production in mouse Prostanoid EP4 receptorEffective concentration which increases intracellular c-AMP production in mouse Prostanoid EP4 receptor

Partial agonist activity at human EP4 receptor expressed in HEK293-AEQ17 cells assessed as cAMP accumulation by aequorin luminescence assayPartial agonist activity at human EP4 receptor expressed in HEK293-AEQ17 cells assessed as cAMP accumulation by aequorin luminescence assay

Effective concentration for increased intracellular c-AMP production by mouse Prostanoid EP4 receptorEffective concentration for increased intracellular c-AMP production by mouse Prostanoid EP4 receptor

Effective concentration for increased intracellular c-AMP production by mouse Prostanoid EP4 receptorEffective concentration for increased intracellular c-AMP production by mouse Prostanoid EP4 receptor

Agonist activity at human recombinant EP4 receptor expressed in HEK293 cells assessed as effect on calcium accumulation by Fluo-4 AM dye based FLIPR assayAgonist activity at human recombinant EP4 receptor expressed in HEK293 cells assessed as effect on calcium accumulation by Fluo-4 AM dye based FLIPR assay

Activity at rat EP4 transfected in HEK293 cells by cAMP accumulationActivity at rat EP4 transfected in HEK293 cells by cAMP accumulation

Functional activity at human EP4 receptorFunctional activity at human EP4 receptor

Functional activity at human EP4 receptorFunctional activity at human EP4 receptor

Effective concentration required for prostanoid EP4 receptor activity was determinedEffective concentration required for prostanoid EP4 receptor activity was determined

Agonist activity against recombinant prostanoid EP4 receptor stably transfected in CHO cellsAgonist activity against recombinant prostanoid EP4 receptor stably transfected in CHO cells

Agonist activity at rat EP4 receptor expressed in CHO cells assessed as cAMP production after 10 mins by radioimmunoassayAgonist activity at rat EP4 receptor expressed in CHO cells assessed as cAMP production after 10 mins by radioimmunoassay

Effective concentration which increases intracellular c-AMP production in mouse Prostanoid EP4 receptorEffective concentration which increases intracellular c-AMP production in mouse Prostanoid EP4 receptor

Functional activity at human EP4 receptorFunctional activity at human EP4 receptor

cAMP Assay: A 384-well drug plate was prepared to contain test compounds, PGE2 and cAMP in 16 serial dilutions in triplicate, using a Biomek station. HEK-EBNA cells expressing a target PG receptor subtype (EP2 or EP4) were suspended in a stimulation buffer (HBSS, 0.1% BSA, 0.5 mM IBMX and 5 mM HEPES, pH 7.4) in a density of 104 cells/5 μl. The reaction was initiated by mixing 5 μL drug dilutions with 5 μl of HEK-EBNA cells in a well, carried out for 30 min at room temperature, and followed by the addition of 5 μl anti-cAMP acceptor beads in the control buffer with Tween-20 (25 mM NaCl, 0.03% Tween-20, 5 mM HEPES, pH7.4). After 30 min in the dark at room temperature, the mixtures were incubated with 15 μl biotinylated-cAMP/strpavidin donor beads in Lysis/Detection buffer (0.1% BSA, 0.3% Tween-20 and 5 mM HEPES, pH7.4) for 45 min at the room temperature. Fluorescence changes were read using a Fusion-alpha HT microplate reader.cAMP Assay: A 384-well drug plate was prepared to contain test compounds, PGE2 and cAMP in 16 serial dilutions in triplicate, using a Biomek station. HEK-EBNA cells expressing a target PG receptor subtype (EP2 or EP4) were suspended in a stimulation buffer (HBSS, 0.1% BSA, 0.5 mM IBMX and 5 mM HEPES, pH 7.4) in a density of 104 cells/5 μl. The reaction was initiated by mixing 5 μL drug dilutions with 5 μl of HEK-EBNA cells in a well, carried out for 30 min at room temperature, and followed by the addition of 5 μl anti-cAMP acceptor beads in the control buffer with Tween-20 (25 mM NaCl, 0.03% Tween-20, 5 mM HEPES, pH7.4). After 30 min in the dark at room temperature, the mixtures were incubated with 15 μl biotinylated-cAMP/strpavidin donor beads in Lysis/Detection buffer (0.1% BSA, 0.3% Tween-20 and 5 mM HEPES, pH7.4) for 45 min at the room temperature. Fluorescence changes were read using a Fusion-alpha HT microplate reader.

Agonist activity against recombinant prostanoid EP4 receptor stably transfected in CHO cellsAgonist activity against recombinant prostanoid EP4 receptor stably transfected in CHO cells

Agonist activity at human EP4 receptorAgonist activity at human EP4 receptor

Partial agonist activity at human EP4 receptor expressed in HEK293-AEQ17 cells assessed as cAMP accumulation by aequorin luminescence assayPartial agonist activity at human EP4 receptor expressed in HEK293-AEQ17 cells assessed as cAMP accumulation by aequorin luminescence assay

Agonist activity at recombinant human EP4 receptor expressed in CHO cells assessed as increase in intracellular cAMP level by EIAAgonist activity at recombinant human EP4 receptor expressed in CHO cells assessed as increase in intracellular cAMP level by EIA

cAMP Assay: A 384-well drug plate was prepared to contain test compounds, PGE2 and cAMP in 16 serial dilutions in triplicate, using a Biomek station. HEK-EBNA cells expressing a target PG receptor subtype (EP2 or EP4) were suspended in a stimulation buffer (HBSS, 0.1% BSA, 0.5 mM IBMX and 5 mM HEPES, pH 7.4) in a density of 104 cells/5 μl. The reaction was initiated by mixing 5 μL drug dilutions with 5 μl of HEK-EBNA cells in a well, carried out for 30 min at room temperature, and followed by the addition of 5 μl anti-cAMP acceptor beads in the control buffer with Tween-20 (25 mM NaCl, 0.03% Tween-20, 5 mM HEPES, pH7.4). After 30 min in the dark at room temperature, the mixtures were incubated with 15 μl biotinylated-cAMP/strpavidin donor beads in Lysis/Detection buffer (0.1% BSA, 0.3% Tween-20 and 5 mM HEPES, pH7.4) for 45 min at the room temperature. Fluorescence changes were read using a Fusion-alpha HT microplate reader.cAMP Assay: A 384-well drug plate was prepared to contain test compounds, PGE2 and cAMP in 16 serial dilutions in triplicate, using a Biomek station. HEK-EBNA cells expressing a target PG receptor subtype (EP2 or EP4) were suspended in a stimulation buffer (HBSS, 0.1% BSA, 0.5 mM IBMX and 5 mM HEPES, pH 7.4) in a density of 104 cells/5 μl. The reaction was initiated by mixing 5 μL drug dilutions with 5 μl of HEK-EBNA cells in a well, carried out for 30 min at room temperature, and followed by the addition of 5 μl anti-cAMP acceptor beads in the control buffer with Tween-20 (25 mM NaCl, 0.03% Tween-20, 5 mM HEPES, pH7.4). After 30 min in the dark at room temperature, the mixtures were incubated with 15 μl biotinylated-cAMP/strpavidin donor beads in Lysis/Detection buffer (0.1% BSA, 0.3% Tween-20 and 5 mM HEPES, pH7.4) for 45 min at the room temperature. Fluorescence changes were read using a Fusion-alpha HT microplate reader.

Activity at rat EP4 transfected in HEK293 cells by cAMP accumulationActivity at rat EP4 transfected in HEK293 cells by cAMP accumulation

Agonist activity against recombinant prostanoid EP4 receptor stably transfected in CHO cellsAgonist activity against recombinant prostanoid EP4 receptor stably transfected in CHO cells

Agonist activity at human EP4 receptor expressed in HEK293 cells by calcium-5 dye based FLIPR assayAgonist activity at human EP4 receptor expressed in HEK293 cells by calcium-5 dye based FLIPR assay

Agonist activity at rat EP4 receptor expressed in CHO cells assessed as cAMP production after 10 mins by radioimmunoassayAgonist activity at rat EP4 receptor expressed in CHO cells assessed as cAMP production after 10 mins by radioimmunoassay

Agonist activity at rat EP4 receptor expressed in CHO cells assessed as cAMP production after 10 mins by radioimmunoassayAgonist activity at rat EP4 receptor expressed in CHO cells assessed as cAMP production after 10 mins by radioimmunoassay

Agonist activity against recombinant prostanoid EP4 receptor stably transfected in CHO cellsAgonist activity against recombinant prostanoid EP4 receptor stably transfected in CHO cells

Functional activity at human EP4 receptorFunctional activity at human EP4 receptor

Effective concentration for increased intracellular c-AMP production by mouse Prostanoid EP4 receptorEffective concentration for increased intracellular c-AMP production by mouse Prostanoid EP4 receptor

Agonist activity against recombinant prostanoid EP4 receptor stably transfected in CHO cellsAgonist activity against recombinant prostanoid EP4 receptor stably transfected in CHO cells

Radioligand Binding: HEK-293 cells stably expressing the human or feline FP receptor, or EP1, EP2, EP3, or EP4 receptors were washed with TME buffer, scraped from the bottom of the flasks, and homogenized for 30 sec using a Brinkman PT 10/35 polytron. TME buffer was added to achieve a final 40 ml volume in the centrifuge tubes (the composition of TME is 100 mM TRIS base, 20 mM MgCl2, 2M EDTA; 10 N HCl is added to achieve a pH of 7.4).The cell homogenate was centrifuged at 19000 r.p.m. for 20 min at 4 C. using a Beckman Ti-60 rotor. The resultant pellet was resuspended in TME buffer to give a final 1 mg/ml protein concentration, as determined by Biorad assay. Radioligand binding competition assays vs. [3H-]17-phenyl PGF2 (5 nM) were performed in a 100 ul volume for 60 min. Binding reactions were started by adding plasma membrane fraction. The reaction was terminated by the addition of 4 ml ice-cold TRIS-HCl buffer and rapid filtration through glass fiber GF/B filters using a Brandel cell.Radioligand Binding: HEK-293 cells stably expressing the human or feline FP receptor, or EP1, EP2, EP3, or EP4 receptors were washed with TME buffer, scraped from the bottom of the flasks, and homogenized for 30 sec using a Brinkman PT 10/35 polytron. TME buffer was added to achieve a final 40 ml volume in the centrifuge tubes (the composition of TME is 100 mM TRIS base, 20 mM MgCl2, 2M EDTA; 10 N HCl is added to achieve a pH of 7.4).The cell homogenate was centrifuged at 19000 r.p.m. for 20 min at 4 C. using a Beckman Ti-60 rotor. The resultant pellet was resuspended in TME buffer to give a final 1 mg/ml protein concentration, as determined by Biorad assay. Radioligand binding competition assays vs. [3H-]17-phenyl PGF2 (5 nM) were performed in a 100 ul volume for 60 min. Binding reactions were started by adding plasma membrane fraction. The reaction was terminated by the addition of 4 ml ice-cold TRIS-HCl buffer and rapid filtration through glass fiber GF/B filters using a Brandel cell.

cAMP Assay: A 384-well drug plate was prepared to contain test compounds, PGE2 and cAMP in 16 serial dilutions in triplicate, using a Biomek station. HEK-EBNA cells expressing a target PG receptor subtype (EP2 or EP4) were suspended in a stimulation buffer (HBSS, 0.1% BSA, 0.5 mM IBMX and 5 mM HEPES, pH 7.4) in a density of 104 cells/5 μl. The reaction was initiated by mixing 5 μL drug dilutions with 5 μl of HEK-EBNA cells in a well, carried out for 30 min at room temperature, and followed by the addition of 5 μl anti-cAMP acceptor beads in the control buffer with Tween-20 (25 mM NaCl, 0.03% Tween-20, 5 mM HEPES, pH7.4). After 30 min in the dark at room temperature, the mixtures were incubated with 15 μl biotinylated-cAMP/strpavidin donor beads in Lysis/Detection buffer (0.1% BSA, 0.3% Tween-20 and 5 mM HEPES, pH7.4) for 45 min at the room temperature. Fluorescence changes were read using a Fusion-alpha HT microplate reader.cAMP Assay: A 384-well drug plate was prepared to contain test compounds, PGE2 and cAMP in 16 serial dilutions in triplicate, using a Biomek station. HEK-EBNA cells expressing a target PG receptor subtype (EP2 or EP4) were suspended in a stimulation buffer (HBSS, 0.1% BSA, 0.5 mM IBMX and 5 mM HEPES, pH 7.4) in a density of 104 cells/5 μl. The reaction was initiated by mixing 5 μL drug dilutions with 5 μl of HEK-EBNA cells in a well, carried out for 30 min at room temperature, and followed by the addition of 5 μl anti-cAMP acceptor beads in the control buffer with Tween-20 (25 mM NaCl, 0.03% Tween-20, 5 mM HEPES, pH7.4). After 30 min in the dark at room temperature, the mixtures were incubated with 15 μl biotinylated-cAMP/strpavidin donor beads in Lysis/Detection buffer (0.1% BSA, 0.3% Tween-20 and 5 mM HEPES, pH7.4) for 45 min at the room temperature. Fluorescence changes were read using a Fusion-alpha HT microplate reader.

Agonist activity at recombinant human EP4 receptor expressed in CHO cells assessed as increase in intracellular cAMP level by EIAAgonist activity at recombinant human EP4 receptor expressed in CHO cells assessed as increase in intracellular cAMP level by EIA

Agonist activity against recombinant prostanoid EP4 receptor stably transfected in CHO cellsAgonist activity against recombinant prostanoid EP4 receptor stably transfected in CHO cells

Agonist activity at EP4 receptor expressed in HEK293 cells assessed as cAMP accumulationAgonist activity at EP4 receptor expressed in HEK293 cells assessed as cAMP accumulation

Agonist activity at rat EP4 receptor expressed in CHO cells assessed as cAMP production after 10 mins by radioimmunoassayAgonist activity at rat EP4 receptor expressed in CHO cells assessed as cAMP production after 10 mins by radioimmunoassay

Agonist activity at rat EP4 receptor expressed in CHO cells assessed as cAMP production after 10 mins by radioimmunoassayAgonist activity at rat EP4 receptor expressed in CHO cells assessed as cAMP production after 10 mins by radioimmunoassay

Agonist activity at rat EP4 receptor expressed in CHO cells assessed as cAMP production after 10 mins by radioimmunoassayAgonist activity at rat EP4 receptor expressed in CHO cells assessed as cAMP production after 10 mins by radioimmunoassay

Functional activity at human EP4 receptorFunctional activity at human EP4 receptor

cAMP Assay: A 384-well drug plate was prepared to contain test compounds, PGE2 and cAMP in 16 serial dilutions in triplicate, using a Biomek station. HEK-EBNA cells expressing a target PG receptor subtype (EP2 or EP4) were suspended in a stimulation buffer (HBSS, 0.1% BSA, 0.5 mM IBMX and 5 mM HEPES, pH 7.4) in a density of 104 cells/5 μl. The reaction was initiated by mixing 5 μL drug dilutions with 5 μl of HEK-EBNA cells in a well, carried out for 30 min at room temperature, and followed by the addition of 5 μl anti-cAMP acceptor beads in the control buffer with Tween-20 (25 mM NaCl, 0.03% Tween-20, 5 mM HEPES, pH7.4). After 30 min in the dark at room temperature, the mixtures were incubated with 15 μl biotinylated-cAMP/strpavidin donor beads in Lysis/Detection buffer (0.1% BSA, 0.3% Tween-20 and 5 mM HEPES, pH7.4) for 45 min at the room temperature. Fluorescence changes were read using a Fusion-alpha HT microplate reader.cAMP Assay: A 384-well drug plate was prepared to contain test compounds, PGE2 and cAMP in 16 serial dilutions in triplicate, using a Biomek station. HEK-EBNA cells expressing a target PG receptor subtype (EP2 or EP4) were suspended in a stimulation buffer (HBSS, 0.1% BSA, 0.5 mM IBMX and 5 mM HEPES, pH 7.4) in a density of 104 cells/5 μl. The reaction was initiated by mixing 5 μL drug dilutions with 5 μl of HEK-EBNA cells in a well, carried out for 30 min at room temperature, and followed by the addition of 5 μl anti-cAMP acceptor beads in the control buffer with Tween-20 (25 mM NaCl, 0.03% Tween-20, 5 mM HEPES, pH7.4). After 30 min in the dark at room temperature, the mixtures were incubated with 15 μl biotinylated-cAMP/strpavidin donor beads in Lysis/Detection buffer (0.1% BSA, 0.3% Tween-20 and 5 mM HEPES, pH7.4) for 45 min at the room temperature. Fluorescence changes were read using a Fusion-alpha HT microplate reader.

Agonist activity at human EP4 receptor expressed in HEK293 cells by calcium-5 dye based FLIPR assayAgonist activity at human EP4 receptor expressed in HEK293 cells by calcium-5 dye based FLIPR assay

Agonist activity at rat EP4 receptor expressed in CHO cells assessed as cAMP production after 10 mins by radioimmunoassayAgonist activity at rat EP4 receptor expressed in CHO cells assessed as cAMP production after 10 mins by radioimmunoassay

Agonist activity at rat EP4 receptor expressed in CHO cells assessed as cAMP production after 10 mins by radioimmunoassayAgonist activity at rat EP4 receptor expressed in CHO cells assessed as cAMP production after 10 mins by radioimmunoassay

Effective concentration for increased intracellular c-AMP production by mouse Prostanoid EP4 receptorEffective concentration for increased intracellular c-AMP production by mouse Prostanoid EP4 receptor

Agonist activity against recombinant prostanoid EP4 receptor stably transfected in CHO cellsAgonist activity against recombinant prostanoid EP4 receptor stably transfected in CHO cells

Functional activity at human EP4 receptorFunctional activity at human EP4 receptor

Activity at rat EP4 transfected in HEK293 cells by cAMP accumulationActivity at rat EP4 transfected in HEK293 cells by cAMP accumulation

Agonist activity against recombinant prostanoid EP4 receptor stably transfected in CHO cellsAgonist activity against recombinant prostanoid EP4 receptor stably transfected in CHO cells

Effective concentration which increases intracellular c-AMP production in mouse Prostanoid EP4 receptorEffective concentration which increases intracellular c-AMP production in mouse Prostanoid EP4 receptor

Effective concentration required for prostanoid EP4 receptor activity was determinedEffective concentration required for prostanoid EP4 receptor activity was determined

Activity at rat EP4 transfected in HEK293 cells by cAMP accumulationActivity at rat EP4 transfected in HEK293 cells by cAMP accumulation

Agonist activity at rat EP4 receptor expressed in CHO cells assessed as cAMP production after 10 mins by radioimmunoassayAgonist activity at rat EP4 receptor expressed in CHO cells assessed as cAMP production after 10 mins by radioimmunoassay

Radioligand Binding: HEK-293 cells stably expressing the human or feline FP receptor, or EP1, EP2, EP3, or EP4 receptors were washed with TME buffer, scraped from the bottom of the flasks, and homogenized for 30 sec using a Brinkman PT 10/35 polytron. TME buffer was added to achieve a final 40 ml volume in the centrifuge tubes (the composition of TME is 100 mM TRIS base, 20 mM MgCl2, 2M EDTA; 10 N HCl is added to achieve a pH of 7.4).The cell homogenate was centrifuged at 19000 r.p.m. for 20 min at 4 C. using a Beckman Ti-60 rotor. The resultant pellet was resuspended in TME buffer to give a final 1 mg/ml protein concentration, as determined by Biorad assay. Radioligand binding competition assays vs. [3H-]17-phenyl PGF2 (5 nM) were performed in a 100 ul volume for 60 min. Binding reactions were started by adding plasma membrane fraction. The reaction was terminated by the addition of 4 ml ice-cold TRIS-HCl buffer and rapid filtration through glass fiber GF/B filters using a Brandel cell.Radioligand Binding: HEK-293 cells stably expressing the human or feline FP receptor, or EP1, EP2, EP3, or EP4 receptors were washed with TME buffer, scraped from the bottom of the flasks, and homogenized for 30 sec using a Brinkman PT 10/35 polytron. TME buffer was added to achieve a final 40 ml volume in the centrifuge tubes (the composition of TME is 100 mM TRIS base, 20 mM MgCl2, 2M EDTA; 10 N HCl is added to achieve a pH of 7.4).The cell homogenate was centrifuged at 19000 r.p.m. for 20 min at 4 C. using a Beckman Ti-60 rotor. The resultant pellet was resuspended in TME buffer to give a final 1 mg/ml protein concentration, as determined by Biorad assay. Radioligand binding competition assays vs. [3H-]17-phenyl PGF2 (5 nM) were performed in a 100 ul volume for 60 min. Binding reactions were started by adding plasma membrane fraction. The reaction was terminated by the addition of 4 ml ice-cold TRIS-HCl buffer and rapid filtration through glass fiber GF/B filters using a Brandel cell.

cAMP Assay: A 384-well drug plate was prepared to contain test compounds, PGE2 and cAMP in 16 serial dilutions in triplicate, using a Biomek station. HEK-EBNA cells expressing a target PG receptor subtype (EP2 or EP4) were suspended in a stimulation buffer (HBSS, 0.1% BSA, 0.5 mM IBMX and 5 mM HEPES, pH 7.4) in a density of 104 cells/5 μl. The reaction was initiated by mixing 5 μL drug dilutions with 5 μl of HEK-EBNA cells in a well, carried out for 30 min at room temperature, and followed by the addition of 5 μl anti-cAMP acceptor beads in the control buffer with Tween-20 (25 mM NaCl, 0.03% Tween-20, 5 mM HEPES, pH7.4). After 30 min in the dark at room temperature, the mixtures were incubated with 15 μl biotinylated-cAMP/strpavidin donor beads in Lysis/Detection buffer (0.1% BSA, 0.3% Tween-20 and 5 mM HEPES, pH7.4) for 45 min at the room temperature. Fluorescence changes were read using a Fusion-alpha HT microplate reader.cAMP Assay: A 384-well drug plate was prepared to contain test compounds, PGE2 and cAMP in 16 serial dilutions in triplicate, using a Biomek station. HEK-EBNA cells expressing a target PG receptor subtype (EP2 or EP4) were suspended in a stimulation buffer (HBSS, 0.1% BSA, 0.5 mM IBMX and 5 mM HEPES, pH 7.4) in a density of 104 cells/5 μl. The reaction was initiated by mixing 5 μL drug dilutions with 5 μl of HEK-EBNA cells in a well, carried out for 30 min at room temperature, and followed by the addition of 5 μl anti-cAMP acceptor beads in the control buffer with Tween-20 (25 mM NaCl, 0.03% Tween-20, 5 mM HEPES, pH7.4). After 30 min in the dark at room temperature, the mixtures were incubated with 15 μl biotinylated-cAMP/strpavidin donor beads in Lysis/Detection buffer (0.1% BSA, 0.3% Tween-20 and 5 mM HEPES, pH7.4) for 45 min at the room temperature. Fluorescence changes were read using a Fusion-alpha HT microplate reader.

Agonist activity against recombinant prostanoid EP4 receptor stably transfected in CHO cellsAgonist activity against recombinant prostanoid EP4 receptor stably transfected in CHO cells

Functional activity at human EP4 receptorFunctional activity at human EP4 receptor

cAMP Assay: A 384-well drug plate was prepared to contain test compounds, PGE2 and cAMP in 16 serial dilutions in triplicate, using a Biomek station. HEK-EBNA cells expressing a target PG receptor subtype (EP2 or EP4) were suspended in a stimulation buffer (HBSS, 0.1% BSA, 0.5 mM IBMX and 5 mM HEPES, pH 7.4) in a density of 104 cells/5 μl. The reaction was initiated by mixing 5 μL drug dilutions with 5 μl of HEK-EBNA cells in a well, carried out for 30 min at room temperature, and followed by the addition of 5 μl anti-cAMP acceptor beads in the control buffer with Tween-20 (25 mM NaCl, 0.03% Tween-20, 5 mM HEPES, pH7.4). After 30 min in the dark at room temperature, the mixtures were incubated with 15 μl biotinylated-cAMP/strpavidin donor beads in Lysis/Detection buffer (0.1% BSA, 0.3% Tween-20 and 5 mM HEPES, pH7.4) for 45 min at the room temperature. Fluorescence changes were read using a Fusion-alpha HT microplate reader.cAMP Assay: A 384-well drug plate was prepared to contain test compounds, PGE2 and cAMP in 16 serial dilutions in triplicate, using a Biomek station. HEK-EBNA cells expressing a target PG receptor subtype (EP2 or EP4) were suspended in a stimulation buffer (HBSS, 0.1% BSA, 0.5 mM IBMX and 5 mM HEPES, pH 7.4) in a density of 104 cells/5 μl. The reaction was initiated by mixing 5 μL drug dilutions with 5 μl of HEK-EBNA cells in a well, carried out for 30 min at room temperature, and followed by the addition of 5 μl anti-cAMP acceptor beads in the control buffer with Tween-20 (25 mM NaCl, 0.03% Tween-20, 5 mM HEPES, pH7.4). After 30 min in the dark at room temperature, the mixtures were incubated with 15 μl biotinylated-cAMP/strpavidin donor beads in Lysis/Detection buffer (0.1% BSA, 0.3% Tween-20 and 5 mM HEPES, pH7.4) for 45 min at the room temperature. Fluorescence changes were read using a Fusion-alpha HT microplate reader.

Agonist activity at rat EP4 receptor expressed in CHO cells assessed as cAMP production after 10 mins by radioimmunoassayAgonist activity at rat EP4 receptor expressed in CHO cells assessed as cAMP production after 10 mins by radioimmunoassay

Cell Based Assay: Ca2+ signaling studies were performed using a FLIPR TETRA system (Molecular Devices, Sunnyvale, Calif., USA) in the 384-format. This is a high-throughput instrument for cell-based assays to monitor Ca2+ signaling associated with GPCRs and ion channels. Cells were seeded at a density of 5×104 cells/well in BioCoat poly-D-lysine coated, black wall, clear bottom 384-well plates (BD Biosciences, Franklin lakes, NJ, USA) and allowed to attach overnight in an incubator at 37° C. The cells were then washed twice with HBSS-HEPES buffer (Hanks' balanced salt solution without bicarbonate and phenol red, 20 mM HEPES, pH 7.4) using an ELx405 Select CW Microplate Washer (BioTek, Winooski, Vt., USA). After 60 min of dye-loading in the dark using the Ca2+-sensitive dye Fluo-4AM (Invitrogen, Carlsbad, Calif., USA), at a final concentration of 2×10^−6M, the plates were washed 4 times with HBSS-HEPES buffer to remove excess dye and leaving 50 μl of buffer in each well. The plates were then placed in the FLIPR TETRA instrument and allowed to equilibrate at 37° C. AGN-211377 was added in a 25 μl volume to each well to give final concentrations of 0.1 μM, 0.3 μM, 1 μM, 3 μM, 10 μM, and 30 μM; or 0.067 μM, 0.1 μM, 0.2 μM, 0.3 μM, 0.67 μM, and 1 μM for cells over-expressing TP receptors. After 4.5 minutes, a 7-point serial dilution of the standard agonist for the corresponding receptor, in a 25 μl volume was injected at the final concentrations from 10^−11M to 10^−5M in 10-fold serial dilution increments for cells expressing human recombinant DP1, EP1, EP2, EP3, EP4, FP, and IP receptors. The dose range for the standard agonist for human recombinant TP receptors was from 10^−12M to 10^−6M. HBSS-HEPES buffer was used as the negative control for the standard agonists. Cells were excited with LED (light emitting diode) excitation at 470-495 nm and emission was measured through an emission filter at 515-575 nm. Assay plates were read for 3.5 minutes using the FLIPRTETRA.Cell Based Assay: Ca2+ signaling studies were performed using a FLIPR TETRA system (Molecular Devices, Sunnyvale, Calif., USA) in the 384-format. This is a high-throughput instrument for cell-based assays to monitor Ca2+ signaling associated with GPCRs and ion channels. Cells were seeded at a density of 5×104 cells/well in BioCoat poly-D-lysine coated, black wall, clear bottom 384-well plates (BD Biosciences, Franklin lakes, NJ, USA) and allowed to attach overnight in an incubator at 37° C. The cells were then washed twice with HBSS-HEPES buffer (Hanks' balanced salt solution without bicarbonate and phenol red, 20 mM HEPES, pH 7.4) using an ELx405 Select CW Microplate Washer (BioTek, Winooski, Vt., USA). After 60 min of dye-loading in the dark using the Ca2+-sensitive dye Fluo-4AM (Invitrogen, Carlsbad, Calif., USA), at a final concentration of 2×10^−6M, the plates were washed 4 times with HBSS-HEPES buffer to remove excess dye and leaving 50 μl of buffer in each well. The plates were then placed in the FLIPR TETRA instrument and allowed to equilibrate at 37° C. AGN-211377 was added in a 25 μl volume to each well to give final concentrations of 0.1 μM, 0.3 μM, 1 μM, 3 μM, 10 μM, and 30 μM; or 0.067 μM, 0.1 μM, 0.2 μM, 0.3 μM, 0.67 μM, and 1 μM for cells over-expressing TP receptors. After 4.5 minutes, a 7-point serial dilution of the standard agonist for the corresponding receptor, in a 25 μl volume was injected at the final concentrations from 10^−11M to 10^−5M in 10-fold serial dilution increments for cells expressing human recombinant DP1, EP1, EP2, EP3, EP4, FP, and IP receptors. The dose range for the standard agonist for human recombinant TP receptors was from 10^−12M to 10^−6M. HBSS-HEPES buffer was used as the negative control for the standard agonists. Cells were excited with LED (light emitting diode) excitation at 470-495 nm and emission was measured through an emission filter at 515-575 nm. Assay plates were read for 3.5 minutes using the FLIPRTETRA.

Agonist activity at human EP4 receptor expressed in HEK293T/17 cells assessed as increase in intracellular cAMP level incubated for 30 mins by ELISAAgonist activity at human EP4 receptor expressed in HEK293T/17 cells assessed as increase in intracellular cAMP level incubated for 30 mins by ELISA

Partial agonist activity at human EP4 receptor expressed in HEK293-AEQ17 cells assessed as cAMP accumulation by aequorin luminescence assayPartial agonist activity at human EP4 receptor expressed in HEK293-AEQ17 cells assessed as cAMP accumulation by aequorin luminescence assay

Partial agonist activity at human EP4 receptor expressed in HEK293-AEQ17 cells assessed as cAMP accumulation by aequorin luminescence assayPartial agonist activity at human EP4 receptor expressed in HEK293-AEQ17 cells assessed as cAMP accumulation by aequorin luminescence assay

Effective concentration required for prostanoid EP4 receptor activity was determinedEffective concentration required for prostanoid EP4 receptor activity was determined

Agonist activity at human EP4 receptor expressed in CHO cells assessed as increase in intracellular cAMP level after 30 mins by HTRF methodAgonist activity at human EP4 receptor expressed in CHO cells assessed as increase in intracellular cAMP level after 30 mins by HTRF method

Activity at rat EP4 transfected in HEK293 cells by cAMP accumulationActivity at rat EP4 transfected in HEK293 cells by cAMP accumulation

Agonist activity at human EP4 receptorAgonist activity at human EP4 receptor

cAMP Assay: 1. Seed cells on an EP2 or EP4 STEP plate at a density of 40,000-80,000 cells/well in 200 uL of reduced serum medium containing 0.5% FBS. Place the plate in a 37° C. incubator with 5% CO2 and incubate overnight. 2. After 16-18 hours of incubation, aspirate the culture media from each well. 3. Add 200 ul of culture medium containing 500 uM IBMX (an inhibitor of cAMP phosphodiesterase) and different concentration of test compounds to the assigned wells. For each test compound, at least 8 concentrations starting at highest 10 M and lowest 0.01 pM were tested. In addition each concentration had triplicates. A PGE2 curve (concentrations from lowest to highest, 0 pM, 0.384 pM, 1.92 pM, 9.6 pM, 48 pM, 240 pM, 1200 pM, and 6000 pM) was always run in parallel with test compounds. 4. Incubate the cells in a cell culture incubator for 30 minutes. 5. Centrifuge the plate at 1,000x rpm for 10 minutes. 6. Aspirate the supernatant.cAMP Assay: 1. Seed cells on an EP2 or EP4 STEP plate at a density of 40,000-80,000 cells/well in 200 uL of reduced serum medium containing 0.5% FBS. Place the plate in a 37° C. incubator with 5% CO2 and incubate overnight. 2. After 16-18 hours of incubation, aspirate the culture media from each well. 3. Add 200 ul of culture medium containing 500 uM IBMX (an inhibitor of cAMP phosphodiesterase) and different concentration of test compounds to the assigned wells. For each test compound, at least 8 concentrations starting at highest 10 M and lowest 0.01 pM were tested. In addition each concentration had triplicates. A PGE2 curve (concentrations from lowest to highest, 0 pM, 0.384 pM, 1.92 pM, 9.6 pM, 48 pM, 240 pM, 1200 pM, and 6000 pM) was always run in parallel with test compounds. 4. Incubate the cells in a cell culture incubator for 30 minutes. 5. Centrifuge the plate at 1,000x rpm for 10 minutes. 6. Aspirate the supernatant.

Partial agonist activity at human EP4 receptor expressed in HEK293-AEQ17 cells assessed as cAMP accumulation by aequorin luminescence assayPartial agonist activity at human EP4 receptor expressed in HEK293-AEQ17 cells assessed as cAMP accumulation by aequorin luminescence assay

Partial agonist activity at human EP4 receptor expressed in HEK293-AEQ17 cells assessed as cAMP accumulation by aequorin luminescence assayPartial agonist activity at human EP4 receptor expressed in HEK293-AEQ17 cells assessed as cAMP accumulation by aequorin luminescence assay

Agonist activity at EP4 receptor expressed in HEK293 cells assessed as cAMP accumulationAgonist activity at EP4 receptor expressed in HEK293 cells assessed as cAMP accumulation

Agonist activity at rat EP4 receptorAgonist activity at rat EP4 receptor

cAMP Assay: A 384-well drug plate was prepared to contain test compounds, PGE2 and cAMP in 16 serial dilutions in triplicate, using a Biomek station. HEK-EBNA cells expressing a target PG receptor subtype (EP2 or EP4) were suspended in a stimulation buffer (HBSS, 0.1% BSA, 0.5 mM IBMX and 5 mM HEPES, pH 7.4) in a density of 104 cells/5 μl. The reaction was initiated by mixing 5 μL drug dilutions with 5 μl of HEK-EBNA cells in a well, carried out for 30 min at room temperature, and followed by the addition of 5 μl anti-cAMP acceptor beads in the control buffer with Tween-20 (25 mM NaCl, 0.03% Tween-20, 5 mM HEPES, pH7.4). After 30 min in the dark at room temperature, the mixtures were incubated with 15 μl biotinylated-cAMP/strpavidin donor beads in Lysis/Detection buffer (0.1% BSA, 0.3% Tween-20 and 5 mM HEPES, pH7.4) for 45 min at the room temperature. Fluorescence changes were read using a Fusion-alpha HT microplate reader.cAMP Assay: A 384-well drug plate was prepared to contain test compounds, PGE2 and cAMP in 16 serial dilutions in triplicate, using a Biomek station. HEK-EBNA cells expressing a target PG receptor subtype (EP2 or EP4) were suspended in a stimulation buffer (HBSS, 0.1% BSA, 0.5 mM IBMX and 5 mM HEPES, pH 7.4) in a density of 104 cells/5 μl. The reaction was initiated by mixing 5 μL drug dilutions with 5 μl of HEK-EBNA cells in a well, carried out for 30 min at room temperature, and followed by the addition of 5 μl anti-cAMP acceptor beads in the control buffer with Tween-20 (25 mM NaCl, 0.03% Tween-20, 5 mM HEPES, pH7.4). After 30 min in the dark at room temperature, the mixtures were incubated with 15 μl biotinylated-cAMP/strpavidin donor beads in Lysis/Detection buffer (0.1% BSA, 0.3% Tween-20 and 5 mM HEPES, pH7.4) for 45 min at the room temperature. Fluorescence changes were read using a Fusion-alpha HT microplate reader.

cAMP Assay: A 384-well drug plate was prepared to contain test compounds, PGE2 and cAMP in 16 serial dilutions in triplicate, using a Biomek station. HEK-EBNA cells expressing a target PG receptor subtype (EP2 or EP4) were suspended in a stimulation buffer (HBSS, 0.1% BSA, 0.5 mM IBMX and 5 mM HEPES, pH 7.4) in a density of 104 cells/5 μl. The reaction was initiated by mixing 5 μL drug dilutions with 5 μl of HEK-EBNA cells in a well, carried out for 30 min at room temperature, and followed by the addition of 5 μl anti-cAMP acceptor beads in the control buffer with Tween-20 (25 mM NaCl, 0.03% Tween-20, 5 mM HEPES, pH7.4). After 30 min in the dark at room temperature, the mixtures were incubated with 15 μl biotinylated-cAMP/strpavidin donor beads in Lysis/Detection buffer (0.1% BSA, 0.3% Tween-20 and 5 mM HEPES, pH7.4) for 45 min at the room temperature. Fluorescence changes were read using a Fusion-alpha HT microplate reader.cAMP Assay: A 384-well drug plate was prepared to contain test compounds, PGE2 and cAMP in 16 serial dilutions in triplicate, using a Biomek station. HEK-EBNA cells expressing a target PG receptor subtype (EP2 or EP4) were suspended in a stimulation buffer (HBSS, 0.1% BSA, 0.5 mM IBMX and 5 mM HEPES, pH 7.4) in a density of 104 cells/5 μl. The reaction was initiated by mixing 5 μL drug dilutions with 5 μl of HEK-EBNA cells in a well, carried out for 30 min at room temperature, and followed by the addition of 5 μl anti-cAMP acceptor beads in the control buffer with Tween-20 (25 mM NaCl, 0.03% Tween-20, 5 mM HEPES, pH7.4). After 30 min in the dark at room temperature, the mixtures were incubated with 15 μl biotinylated-cAMP/strpavidin donor beads in Lysis/Detection buffer (0.1% BSA, 0.3% Tween-20 and 5 mM HEPES, pH7.4) for 45 min at the room temperature. Fluorescence changes were read using a Fusion-alpha HT microplate reader.

Agonist activity at rat EP4 receptor expressed in CHO cells assessed as cAMP production after 10 mins by radioimmunoassayAgonist activity at rat EP4 receptor expressed in CHO cells assessed as cAMP production after 10 mins by radioimmunoassay

Activity at rat EP4 transfected in HEK293 cells by cAMP accumulationActivity at rat EP4 transfected in HEK293 cells by cAMP accumulation

Agonist activity at rat EP4 receptor expressed in CHO cells assessed as cAMP production after 10 mins by radioimmunoassayAgonist activity at rat EP4 receptor expressed in CHO cells assessed as cAMP production after 10 mins by radioimmunoassay

EP4 agonist potency utilizing a stable clone of pSV40-EP4 transfected into HEK293 cells expressing EP4 receptorEP4 agonist potency utilizing a stable clone of pSV40-EP4 transfected into HEK293 cells expressing EP4 receptor

Effective concentration for increased intracellular c-AMP production by mouse Prostanoid EP4 receptorEffective concentration for increased intracellular c-AMP production by mouse Prostanoid EP4 receptor

Effective concentration which increases intracellular c-AMP production in mouse Prostanoid EP4 receptorEffective concentration which increases intracellular c-AMP production in mouse Prostanoid EP4 receptor

Effective concentration which increases intracellular c-AMP production in mouse Prostanoid EP4 receptorEffective concentration which increases intracellular c-AMP production in mouse Prostanoid EP4 receptor

Agonist activity at rabbit EP4 receptor assessed as relaxation of Kcl-induced tissue contraction by isometric transducer methodAgonist activity at rabbit EP4 receptor assessed as relaxation of Kcl-induced tissue contraction by isometric transducer method

Agonist activity at human EP4 receptor expressed in HEK293T/17 cells assessed as increase in intracellular cAMP level incubated for 30 mins by ELISAAgonist activity at human EP4 receptor expressed in HEK293T/17 cells assessed as increase in intracellular cAMP level incubated for 30 mins by ELISA

Effective concentration which increases intracellular c-AMP production in mouse Prostanoid EP4 receptorEffective concentration which increases intracellular c-AMP production in mouse Prostanoid EP4 receptor

Effective concentration for increased intracellular c-AMP production by mouse Prostanoid EP4 receptorEffective concentration for increased intracellular c-AMP production by mouse Prostanoid EP4 receptor

Agonist activity against recombinant prostanoid EP4 receptor stably transfected in CHO cellsAgonist activity against recombinant prostanoid EP4 receptor stably transfected in CHO cells

Activity at rat EP4 transfected in HEK293 cells by cAMP accumulationActivity at rat EP4 transfected in HEK293 cells by cAMP accumulation

Agonist activity at EP4 receptor expressed in HEK293 cells assessed as cAMP accumulationAgonist activity at EP4 receptor expressed in HEK293 cells assessed as cAMP accumulation

Agonist activity at rat EP4 receptor expressed in CHO cells assessed as cAMP production after 10 mins by radioimmunoassayAgonist activity at rat EP4 receptor expressed in CHO cells assessed as cAMP production after 10 mins by radioimmunoassay

cAMP Assay: A 384-well drug plate was prepared to contain test compounds, PGE2 and cAMP in 16 serial dilutions in triplicate, using a Biomek station. HEK-EBNA cells expressing a target PG receptor subtype (EP2 or EP4) were suspended in a stimulation buffer (HBSS, 0.1% BSA, 0.5 mM IBMX and 5 mM HEPES, pH 7.4) in a density of 104 cells/5 μl. The reaction was initiated by mixing 5 μL drug dilutions with 5 μl of HEK-EBNA cells in a well, carried out for 30 min at room temperature, and followed by the addition of 5 μl anti-cAMP acceptor beads in the control buffer with Tween-20 (25 mM NaCl, 0.03% Tween-20, 5 mM HEPES, pH7.4). After 30 min in the dark at room temperature, the mixtures were incubated with 15 μl biotinylated-cAMP/strpavidin donor beads in Lysis/Detection buffer (0.1% BSA, 0.3% Tween-20 and 5 mM HEPES, pH7.4) for 45 min at the room temperature. Fluorescence changes were read using a Fusion-alpha HT microplate reader.cAMP Assay: A 384-well drug plate was prepared to contain test compounds, PGE2 and cAMP in 16 serial dilutions in triplicate, using a Biomek station. HEK-EBNA cells expressing a target PG receptor subtype (EP2 or EP4) were suspended in a stimulation buffer (HBSS, 0.1% BSA, 0.5 mM IBMX and 5 mM HEPES, pH 7.4) in a density of 104 cells/5 μl. The reaction was initiated by mixing 5 μL drug dilutions with 5 μl of HEK-EBNA cells in a well, carried out for 30 min at room temperature, and followed by the addition of 5 μl anti-cAMP acceptor beads in the control buffer with Tween-20 (25 mM NaCl, 0.03% Tween-20, 5 mM HEPES, pH7.4). After 30 min in the dark at room temperature, the mixtures were incubated with 15 μl biotinylated-cAMP/strpavidin donor beads in Lysis/Detection buffer (0.1% BSA, 0.3% Tween-20 and 5 mM HEPES, pH7.4) for 45 min at the room temperature. Fluorescence changes were read using a Fusion-alpha HT microplate reader.

cAMP Assay: A 384-well drug plate was prepared to contain test compounds, PGE2 and cAMP in 16 serial dilutions in triplicate, using a Biomek station. HEK-EBNA cells expressing a target PG receptor subtype (EP2 or EP4) were suspended in a stimulation buffer (HBSS, 0.1% BSA, 0.5 mM IBMX and 5 mM HEPES, pH 7.4) in a density of 104 cells/5 μl. The reaction was initiated by mixing 5 μL drug dilutions with 5 μl of HEK-EBNA cells in a well, carried out for 30 min at room temperature, and followed by the addition of 5 μl anti-cAMP acceptor beads in the control buffer with Tween-20 (25 mM NaCl, 0.03% Tween-20, 5 mM HEPES, pH7.4). After 30 min in the dark at room temperature, the mixtures were incubated with 15 μl biotinylated-cAMP/strpavidin donor beads in Lysis/Detection buffer (0.1% BSA, 0.3% Tween-20 and 5 mM HEPES, pH7.4) for 45 min at the room temperature. Fluorescence changes were read using a Fusion-alpha HT microplate reader.cAMP Assay: A 384-well drug plate was prepared to contain test compounds, PGE2 and cAMP in 16 serial dilutions in triplicate, using a Biomek station. HEK-EBNA cells expressing a target PG receptor subtype (EP2 or EP4) were suspended in a stimulation buffer (HBSS, 0.1% BSA, 0.5 mM IBMX and 5 mM HEPES, pH 7.4) in a density of 104 cells/5 μl. The reaction was initiated by mixing 5 μL drug dilutions with 5 μl of HEK-EBNA cells in a well, carried out for 30 min at room temperature, and followed by the addition of 5 μl anti-cAMP acceptor beads in the control buffer with Tween-20 (25 mM NaCl, 0.03% Tween-20, 5 mM HEPES, pH7.4). After 30 min in the dark at room temperature, the mixtures were incubated with 15 μl biotinylated-cAMP/strpavidin donor beads in Lysis/Detection buffer (0.1% BSA, 0.3% Tween-20 and 5 mM HEPES, pH7.4) for 45 min at the room temperature. Fluorescence changes were read using a Fusion-alpha HT microplate reader.

Functional activity at human EP4 receptorFunctional activity at human EP4 receptor

Effective concentration required for prostanoid EP4 receptor activity was determinedEffective concentration required for prostanoid EP4 receptor activity was determined

Activity at rat EP4 transfected in HEK293 cells by cAMP accumulationActivity at rat EP4 transfected in HEK293 cells by cAMP accumulation

Agonist activity at human recombinant EP4 receptor expressed in HEK293 cells assessed as effect on calcium accumulation by Fluo-4 AM dye based FLIPR assayAgonist activity at human recombinant EP4 receptor expressed in HEK293 cells assessed as effect on calcium accumulation by Fluo-4 AM dye based FLIPR assay

Agonist activity at rat EP4 receptor expressed in CHO cells assessed as cAMP production after 10 mins by radioimmunoassayAgonist activity at rat EP4 receptor expressed in CHO cells assessed as cAMP production after 10 mins by radioimmunoassay

Agonist activity at rat EP4 receptor expressed in CHO cells assessed as cAMP production after 10 mins by radioimmunoassayAgonist activity at rat EP4 receptor expressed in CHO cells assessed as cAMP production after 10 mins by radioimmunoassay

Agonist activity at human EP4 receptorAgonist activity at human EP4 receptor

Partial agonist activity at human EP4 receptor expressed in HEK293-AEQ17 cells assessed as cAMP accumulation by aequorin luminescence assayPartial agonist activity at human EP4 receptor expressed in HEK293-AEQ17 cells assessed as cAMP accumulation by aequorin luminescence assay

Partial agonist activity at human EP4 receptor expressed in HEK293-AEQ17 cells assessed as cAMP accumulation by aequorin luminescence assayPartial agonist activity at human EP4 receptor expressed in HEK293-AEQ17 cells assessed as cAMP accumulation by aequorin luminescence assay

Agonist activity at recombinant human EP4 receptor expressed in CHO cells assessed as increase in intracellular cAMP level by EIAAgonist activity at recombinant human EP4 receptor expressed in CHO cells assessed as increase in intracellular cAMP level by EIA

Agonist activity at rat EP4 receptor expressed in CHO cells assessed as cAMP production after 10 mins by radioimmunoassayAgonist activity at rat EP4 receptor expressed in CHO cells assessed as cAMP production after 10 mins by radioimmunoassay

Agonist activity at recombinant human EP4 receptor expressed in CHO cells assessed as increase in intracellular cAMP level by EIAAgonist activity at recombinant human EP4 receptor expressed in CHO cells assessed as increase in intracellular cAMP level by EIA

Effective concentration required for prostanoid EP4 receptor activity was determinedEffective concentration required for prostanoid EP4 receptor activity was determined

Agonist activity at recombinant human EP4 receptor expressed in CHO cells assessed as increase in intracellular cAMP level by EIAAgonist activity at recombinant human EP4 receptor expressed in CHO cells assessed as increase in intracellular cAMP level by EIA

Radioligand Binding: HEK-293 cells stably expressing the human or feline FP receptor, or EP1, EP2, EP3, or EP4 receptors were washed with TME buffer, scraped from the bottom of the flasks, and homogenized for 30 sec using a Brinkman PT 10/35 polytron. TME buffer was added to achieve a final 40 ml volume in the centrifuge tubes (the composition of TME is 100 mM TRIS base, 20 mM MgCl2, 2M EDTA; 10 N HCl is added to achieve a pH of 7.4).The cell homogenate was centrifuged at 19000 r.p.m. for 20 min at 4 C. using a Beckman Ti-60 rotor. The resultant pellet was resuspended in TME buffer to give a final 1 mg/ml protein concentration, as determined by Biorad assay. Radioligand binding competition assays vs. [3H-]17-phenyl PGF2 (5 nM) were performed in a 100 ul volume for 60 min. Binding reactions were started by adding plasma membrane fraction. The reaction was terminated by the addition of 4 ml ice-cold TRIS-HCl buffer and rapid filtration through glass fiber GF/B filters using a Brandel cell.Radioligand Binding: HEK-293 cells stably expressing the human or feline FP receptor, or EP1, EP2, EP3, or EP4 receptors were washed with TME buffer, scraped from the bottom of the flasks, and homogenized for 30 sec using a Brinkman PT 10/35 polytron. TME buffer was added to achieve a final 40 ml volume in the centrifuge tubes (the composition of TME is 100 mM TRIS base, 20 mM MgCl2, 2M EDTA; 10 N HCl is added to achieve a pH of 7.4).The cell homogenate was centrifuged at 19000 r.p.m. for 20 min at 4 C. using a Beckman Ti-60 rotor. The resultant pellet was resuspended in TME buffer to give a final 1 mg/ml protein concentration, as determined by Biorad assay. Radioligand binding competition assays vs. [3H-]17-phenyl PGF2 (5 nM) were performed in a 100 ul volume for 60 min. Binding reactions were started by adding plasma membrane fraction. The reaction was terminated by the addition of 4 ml ice-cold TRIS-HCl buffer and rapid filtration through glass fiber GF/B filters using a Brandel cell.

Agonist activity at rat EP4 receptorAgonist activity at rat EP4 receptor

Agonist activity at rat EP4 receptor expressed in CHO cells assessed as cAMP production after 10 mins by radioimmunoassayAgonist activity at rat EP4 receptor expressed in CHO cells assessed as cAMP production after 10 mins by radioimmunoassay

Agonist activity at rat EP4 receptor expressed in CHO cells assessed as cAMP production after 10 mins by radioimmunoassayAgonist activity at rat EP4 receptor expressed in CHO cells assessed as cAMP production after 10 mins by radioimmunoassay

Effective concentration for increased intracellular c-AMP production by mouse Prostanoid EP4 receptorEffective concentration for increased intracellular c-AMP production by mouse Prostanoid EP4 receptor

Effective concentration which increases intracellular c-AMP production in mouse Prostanoid EP4 receptorEffective concentration which increases intracellular c-AMP production in mouse Prostanoid EP4 receptor

Activity at rat EP4 transfected in HEK293 cells by cAMP accumulationActivity at rat EP4 transfected in HEK293 cells by cAMP accumulation

Agonist activity at human prostaglandin EP4 receptorAgonist activity at human prostaglandin EP4 receptor

Agonist activity at rat EP4 receptor expressed in CHO cells assessed as cAMP production after 10 mins by radioimmunoassayAgonist activity at rat EP4 receptor expressed in CHO cells assessed as cAMP production after 10 mins by radioimmunoassay

Agonist activity at rat EP4 receptor expressed in CHO cells assessed as cAMP production after 10 mins by radioimmunoassayAgonist activity at rat EP4 receptor expressed in CHO cells assessed as cAMP production after 10 mins by radioimmunoassay

Effective concentration required for prostanoid EP4 receptor activity was determinedEffective concentration required for prostanoid EP4 receptor activity was determined

Agonist activity at human EP4 receptor expressed in HEK293 cells by calcium-5 dye based FLIPR assayAgonist activity at human EP4 receptor expressed in HEK293 cells by calcium-5 dye based FLIPR assay

Agonist activity at rat EP4 receptor expressed in CHO cells assessed as cAMP production after 10 mins by radioimmunoassayAgonist activity at rat EP4 receptor expressed in CHO cells assessed as cAMP production after 10 mins by radioimmunoassay

Effective concentration required for prostanoid EP4 receptor activity was determinedEffective concentration required for prostanoid EP4 receptor activity was determined

Agonist activity at EP4 receptor expressed in HEK293 cells assessed as cAMP accumulationAgonist activity at EP4 receptor expressed in HEK293 cells assessed as cAMP accumulation

Agonist activity at human EP4 receptorAgonist activity at human EP4 receptor

Agonist activity at human EP4 receptor by cAMP assayAgonist activity at human EP4 receptor by cAMP assay

Agonist activity at human EP4 receptor by cAMP assayAgonist activity at human EP4 receptor by cAMP assay

EP4 agonist potency utilizing a stable clone of pSV40-EP4 transfected into HEK293 cells expressing EP4 receptorEP4 agonist potency utilizing a stable clone of pSV40-EP4 transfected into HEK293 cells expressing EP4 receptor

Agonist activity at rat EP4 receptorAgonist activity at rat EP4 receptor

Effective concentration which increases intracellular c-AMP production in mouse Prostanoid EP4 receptorEffective concentration which increases intracellular c-AMP production in mouse Prostanoid EP4 receptor

cAMP Assay: 1. Seed cells on an EP2 or EP4 STEP plate at a density of 40,000-80,000 cells/well in 200 uL of reduced serum medium containing 0.5% FBS. Place the plate in a 37° C. incubator with 5% CO2 and incubate overnight. 2. After 16-18 hours of incubation, aspirate the culture media from each well. 3. Add 200 ul of culture medium containing 500 uM IBMX (an inhibitor of cAMP phosphodiesterase) and different concentration of test compounds to the assigned wells. For each test compound, at least 8 concentrations starting at highest 10 M and lowest 0.01 pM were tested. In addition each concentration had triplicates. A PGE2 curve (concentrations from lowest to highest, 0 pM, 0.384 pM, 1.92 pM, 9.6 pM, 48 pM, 240 pM, 1200 pM, and 6000 pM) was always run in parallel with test compounds. 4. Incubate the cells in a cell culture incubator for 30 minutes. 5. Centrifuge the plate at 1,000x rpm for 10 minutes. 6. Aspirate the supernatant.cAMP Assay: 1. Seed cells on an EP2 or EP4 STEP plate at a density of 40,000-80,000 cells/well in 200 uL of reduced serum medium containing 0.5% FBS. Place the plate in a 37° C. incubator with 5% CO2 and incubate overnight. 2. After 16-18 hours of incubation, aspirate the culture media from each well. 3. Add 200 ul of culture medium containing 500 uM IBMX (an inhibitor of cAMP phosphodiesterase) and different concentration of test compounds to the assigned wells. For each test compound, at least 8 concentrations starting at highest 10 M and lowest 0.01 pM were tested. In addition each concentration had triplicates. A PGE2 curve (concentrations from lowest to highest, 0 pM, 0.384 pM, 1.92 pM, 9.6 pM, 48 pM, 240 pM, 1200 pM, and 6000 pM) was always run in parallel with test compounds. 4. Incubate the cells in a cell culture incubator for 30 minutes. 5. Centrifuge the plate at 1,000x rpm for 10 minutes. 6. Aspirate the supernatant.

Agonist activity at rat EP4 receptor expressed in CHO cells assessed as cAMP production after 10 mins by radioimmunoassayAgonist activity at rat EP4 receptor expressed in CHO cells assessed as cAMP production after 10 mins by radioimmunoassay

Effective concentration for increased intracellular c-AMP production by mouse Prostanoid EP4 receptorEffective concentration for increased intracellular c-AMP production by mouse Prostanoid EP4 receptor

Agonist activity at rat EP4 receptorAgonist activity at rat EP4 receptor

Effective concentration for increased intracellular c-AMP production by mouse Prostanoid EP4 receptorEffective concentration for increased intracellular c-AMP production by mouse Prostanoid EP4 receptor

Effective concentration for increased intracellular c-AMP production by mouse Prostanoid EP4 receptorEffective concentration for increased intracellular c-AMP production by mouse Prostanoid EP4 receptor

Effective concentration for increased intracellular c-AMP production by mouse Prostanoid EP4 receptorEffective concentration for increased intracellular c-AMP production by mouse Prostanoid EP4 receptor

Effective concentration which increases intracellular c-AMP production in mouse Prostanoid EP4 receptorEffective concentration which increases intracellular c-AMP production in mouse Prostanoid EP4 receptor

Partial agonist activity at human EP4 receptor expressed in HEK293-AEQ17 cells assessed as cAMP accumulation by aequorin luminescence assayPartial agonist activity at human EP4 receptor expressed in HEK293-AEQ17 cells assessed as cAMP accumulation by aequorin luminescence assay

cAMP Assay: A 384-well drug plate was prepared to contain test compounds, PGE2 and cAMP in 16 serial dilutions in triplicate, using a Biomek station. HEK-EBNA cells expressing a target PG receptor subtype (EP2 or EP4) were suspended in a stimulation buffer (HBSS, 0.1% BSA, 0.5 mM IBMX and 5 mM HEPES, pH 7.4) in a density of 104 cells/5 μl. The reaction was initiated by mixing 5 μL drug dilutions with 5 μl of HEK-EBNA cells in a well, carried out for 30 min at room temperature, and followed by the addition of 5 μl anti-cAMP acceptor beads in the control buffer with Tween-20 (25 mM NaCl, 0.03% Tween-20, 5 mM HEPES, pH7.4). After 30 min in the dark at room temperature, the mixtures were incubated with 15 μl biotinylated-cAMP/strpavidin donor beads in Lysis/Detection buffer (0.1% BSA, 0.3% Tween-20 and 5 mM HEPES, pH7.4) for 45 min at the room temperature. Fluorescence changes were read using a Fusion-alpha HT microplate reader.cAMP Assay: A 384-well drug plate was prepared to contain test compounds, PGE2 and cAMP in 16 serial dilutions in triplicate, using a Biomek station. HEK-EBNA cells expressing a target PG receptor subtype (EP2 or EP4) were suspended in a stimulation buffer (HBSS, 0.1% BSA, 0.5 mM IBMX and 5 mM HEPES, pH 7.4) in a density of 104 cells/5 μl. The reaction was initiated by mixing 5 μL drug dilutions with 5 μl of HEK-EBNA cells in a well, carried out for 30 min at room temperature, and followed by the addition of 5 μl anti-cAMP acceptor beads in the control buffer with Tween-20 (25 mM NaCl, 0.03% Tween-20, 5 mM HEPES, pH7.4). After 30 min in the dark at room temperature, the mixtures were incubated with 15 μl biotinylated-cAMP/strpavidin donor beads in Lysis/Detection buffer (0.1% BSA, 0.3% Tween-20 and 5 mM HEPES, pH7.4) for 45 min at the room temperature. Fluorescence changes were read using a Fusion-alpha HT microplate reader.

Radioligand Binding: HEK-293 cells stably expressing the human or feline FP receptor, or EP1, EP2, EP3, or EP4 receptors were washed with TME buffer, scraped from the bottom of the flasks, and homogenized for 30 sec using a Brinkman PT 10/35 polytron. TME buffer was added to achieve a final 40 ml volume in the centrifuge tubes (the composition of TME is 100 mM TRIS base, 20 mM MgCl2, 2M EDTA; 10 N HCl is added to achieve a pH of 7.4).The cell homogenate was centrifuged at 19000 r.p.m. for 20 min at 4 C. using a Beckman Ti-60 rotor. The resultant pellet was resuspended in TME buffer to give a final 1 mg/ml protein concentration, as determined by Biorad assay. Radioligand binding competition assays vs. [3H-]17-phenyl PGF2 (5 nM) were performed in a 100 ul volume for 60 min. Binding reactions were started by adding plasma membrane fraction. The reaction was terminated by the addition of 4 ml ice-cold TRIS-HCl buffer and rapid filtration through glass fiber GF/B filters using a Brandel cell.Radioligand Binding: HEK-293 cells stably expressing the human or feline FP receptor, or EP1, EP2, EP3, or EP4 receptors were washed with TME buffer, scraped from the bottom of the flasks, and homogenized for 30 sec using a Brinkman PT 10/35 polytron. TME buffer was added to achieve a final 40 ml volume in the centrifuge tubes (the composition of TME is 100 mM TRIS base, 20 mM MgCl2, 2M EDTA; 10 N HCl is added to achieve a pH of 7.4).The cell homogenate was centrifuged at 19000 r.p.m. for 20 min at 4 C. using a Beckman Ti-60 rotor. The resultant pellet was resuspended in TME buffer to give a final 1 mg/ml protein concentration, as determined by Biorad assay. Radioligand binding competition assays vs. [3H-]17-phenyl PGF2 (5 nM) were performed in a 100 ul volume for 60 min. Binding reactions were started by adding plasma membrane fraction. The reaction was terminated by the addition of 4 ml ice-cold TRIS-HCl buffer and rapid filtration through glass fiber GF/B filters using a Brandel cell.

Radioligand Binding: HEK-293 cells stably expressing the human or feline FP receptor, or EP1, EP2, EP3, or EP4 receptors were washed with TME buffer, scraped from the bottom of the flasks, and homogenized for 30 sec using a Brinkman PT 10/35 polytron. TME buffer was added to achieve a final 40 ml volume in the centrifuge tubes (the composition of TME is 100 mM TRIS base, 20 mM MgCl2, 2M EDTA; 10 N HCl is added to achieve a pH of 7.4).The cell homogenate was centrifuged at 19000 r.p.m. for 20 min at 4 C. using a Beckman Ti-60 rotor. The resultant pellet was resuspended in TME buffer to give a final 1 mg/ml protein concentration, as determined by Biorad assay. Radioligand binding competition assays vs. [3H-]17-phenyl PGF2 (5 nM) were performed in a 100 ul volume for 60 min. Binding reactions were started by adding plasma membrane fraction. The reaction was terminated by the addition of 4 ml ice-cold TRIS-HCl buffer and rapid filtration through glass fiber GF/B filters using a Brandel cell.Radioligand Binding: HEK-293 cells stably expressing the human or feline FP receptor, or EP1, EP2, EP3, or EP4 receptors were washed with TME buffer, scraped from the bottom of the flasks, and homogenized for 30 sec using a Brinkman PT 10/35 polytron. TME buffer was added to achieve a final 40 ml volume in the centrifuge tubes (the composition of TME is 100 mM TRIS base, 20 mM MgCl2, 2M EDTA; 10 N HCl is added to achieve a pH of 7.4).The cell homogenate was centrifuged at 19000 r.p.m. for 20 min at 4 C. using a Beckman Ti-60 rotor. The resultant pellet was resuspended in TME buffer to give a final 1 mg/ml protein concentration, as determined by Biorad assay. Radioligand binding competition assays vs. [3H-]17-phenyl PGF2 (5 nM) were performed in a 100 ul volume for 60 min. Binding reactions were started by adding plasma membrane fraction. The reaction was terminated by the addition of 4 ml ice-cold TRIS-HCl buffer and rapid filtration through glass fiber GF/B filters using a Brandel cell.

Effective concentration which increases intracellular c-AMP production in mouse Prostanoid EP4 receptorEffective concentration which increases intracellular c-AMP production in mouse Prostanoid EP4 receptor

Radioligand Binding: HEK-293 cells stably expressing the human or feline FP receptor, or EP1, EP2, EP3, or EP4 receptors were washed with TME buffer, scraped from the bottom of the flasks, and homogenized for 30 sec using a Brinkman PT 10/35 polytron. TME buffer was added to achieve a final 40 ml volume in the centrifuge tubes (the composition of TME is 100 mM TRIS base, 20 mM MgCl2, 2M EDTA; 10 N HCl is added to achieve a pH of 7.4).The cell homogenate was centrifuged at 19000 r.p.m. for 20 min at 4 C. using a Beckman Ti-60 rotor. The resultant pellet was resuspended in TME buffer to give a final 1 mg/ml protein concentration, as determined by Biorad assay. Radioligand binding competition assays vs. [3H-]17-phenyl PGF2 (5 nM) were performed in a 100 ul volume for 60 min. Binding reactions were started by adding plasma membrane fraction. The reaction was terminated by the addition of 4 ml ice-cold TRIS-HCl buffer and rapid filtration through glass fiber GF/B filters using a Brandel cell.Radioligand Binding: HEK-293 cells stably expressing the human or feline FP receptor, or EP1, EP2, EP3, or EP4 receptors were washed with TME buffer, scraped from the bottom of the flasks, and homogenized for 30 sec using a Brinkman PT 10/35 polytron. TME buffer was added to achieve a final 40 ml volume in the centrifuge tubes (the composition of TME is 100 mM TRIS base, 20 mM MgCl2, 2M EDTA; 10 N HCl is added to achieve a pH of 7.4).The cell homogenate was centrifuged at 19000 r.p.m. for 20 min at 4 C. using a Beckman Ti-60 rotor. The resultant pellet was resuspended in TME buffer to give a final 1 mg/ml protein concentration, as determined by Biorad assay. Radioligand binding competition assays vs. [3H-]17-phenyl PGF2 (5 nM) were performed in a 100 ul volume for 60 min. Binding reactions were started by adding plasma membrane fraction. The reaction was terminated by the addition of 4 ml ice-cold TRIS-HCl buffer and rapid filtration through glass fiber GF/B filters using a Brandel cell.

Activity at rat EP4 transfected in HEK293 cells by cAMP accumulationActivity at rat EP4 transfected in HEK293 cells by cAMP accumulation

Agonist activity at human EP4 receptorAgonist activity at human EP4 receptor

Agonist activity at human EP4 receptor expressed in CHO cells assessed as increase in intracellular cAMP level after 30 mins by HTRF methodAgonist activity at human EP4 receptor expressed in CHO cells assessed as increase in intracellular cAMP level after 30 mins by HTRF method

Agonist activity at rat EP4 receptor expressed in CHO cells assessed as cAMP production after 10 mins by radioimmunoassayAgonist activity at rat EP4 receptor expressed in CHO cells assessed as cAMP production after 10 mins by radioimmunoassay

Agonist activity at recombinant human EP4 receptor expressed in CHO cells assessed as increase in intracellular cAMP level by EIAAgonist activity at recombinant human EP4 receptor expressed in CHO cells assessed as increase in intracellular cAMP level by EIA

Agonist activity at recombinant human EP4 receptor expressed in CHO cells assessed as increase in intracellular cAMP level by EIAAgonist activity at recombinant human EP4 receptor expressed in CHO cells assessed as increase in intracellular cAMP level by EIA

Effective concentration required for prostanoid EP4 receptor activity was determinedEffective concentration required for prostanoid EP4 receptor activity was determined

Effective concentration which increases intracellular c-AMP production in mouse Prostanoid EP4 receptorEffective concentration which increases intracellular c-AMP production in mouse Prostanoid EP4 receptor

Agonist activity at rat EP4 receptor expressed in CHO cells assessed as cAMP production after 10 mins by radioimmunoassayAgonist activity at rat EP4 receptor expressed in CHO cells assessed as cAMP production after 10 mins by radioimmunoassay

Agonist activity at rat EP4 receptor expressed in CHO cells assessed as cAMP production after 10 mins by radioimmunoassayAgonist activity at rat EP4 receptor expressed in CHO cells assessed as cAMP production after 10 mins by radioimmunoassay

Agonist activity against recombinant prostanoid EP4 receptor stably transfected in CHO cellsAgonist activity against recombinant prostanoid EP4 receptor stably transfected in CHO cells

Agonist activity at human EP4 receptor expressed in HEK293 cells by calcium-5 dye based FLIPR assayAgonist activity at human EP4 receptor expressed in HEK293 cells by calcium-5 dye based FLIPR assay

Cell Based Assay: Ca2+ signaling studies were performed using a FLIPR TETRA system (Molecular Devices, Sunnyvale, Calif., USA) in the 384-format. This is a high-throughput instrument for cell-based assays to monitor Ca2+ signaling associated with GPCRs and ion channels. Cells were seeded at a density of 5×104 cells/well in BioCoat poly-D-lysine coated, black wall, clear bottom 384-well plates (BD Biosciences, Franklin lakes, NJ, USA) and allowed to attach overnight in an incubator at 37° C. The cells were then washed twice with HBSS-HEPES buffer (Hanks' balanced salt solution without bicarbonate and phenol red, 20 mM HEPES, pH 7.4) using an ELx405 Select CW Microplate Washer (BioTek, Winooski, Vt., USA). After 60 min of dye-loading in the dark using the Ca2+-sensitive dye Fluo-4AM (Invitrogen, Carlsbad, Calif., USA), at a final concentration of 2×10^−6M, the plates were washed 4 times with HBSS-HEPES buffer to remove excess dye and leaving 50 μl of buffer in each well. The plates were then placed in the FLIPR TETRA instrument and allowed to equilibrate at 37° C. AGN-211377 was added in a 25 μl volume to each well to give final concentrations of 0.1 μM, 0.3 μM, 1 μM, 3 μM, 10 μM, and 30 μM; or 0.067 μM, 0.1 μM, 0.2 μM, 0.3 μM, 0.67 μM, and 1 μM for cells over-expressing TP receptors. After 4.5 minutes, a 7-point serial dilution of the standard agonist for the corresponding receptor, in a 25 μl volume was injected at the final concentrations from 10^−11M to 10^−5M in 10-fold serial dilution increments for cells expressing human recombinant DP1, EP1, EP2, EP3, EP4, FP, and IP receptors. The dose range for the standard agonist for human recombinant TP receptors was from 10^−12M to 10^−6M. HBSS-HEPES buffer was used as the negative control for the standard agonists. Cells were excited with LED (light emitting diode) excitation at 470-495 nm and emission was measured through an emission filter at 515-575 nm. Assay plates were read for 3.5 minutes using the FLIPRTETRA.Cell Based Assay: Ca2+ signaling studies were performed using a FLIPR TETRA system (Molecular Devices, Sunnyvale, Calif., USA) in the 384-format. This is a high-throughput instrument for cell-based assays to monitor Ca2+ signaling associated with GPCRs and ion channels. Cells were seeded at a density of 5×104 cells/well in BioCoat poly-D-lysine coated, black wall, clear bottom 384-well plates (BD Biosciences, Franklin lakes, NJ, USA) and allowed to attach overnight in an incubator at 37° C. The cells were then washed twice with HBSS-HEPES buffer (Hanks' balanced salt solution without bicarbonate and phenol red, 20 mM HEPES, pH 7.4) using an ELx405 Select CW Microplate Washer (BioTek, Winooski, Vt., USA). After 60 min of dye-loading in the dark using the Ca2+-sensitive dye Fluo-4AM (Invitrogen, Carlsbad, Calif., USA), at a final concentration of 2×10^−6M, the plates were washed 4 times with HBSS-HEPES buffer to remove excess dye and leaving 50 μl of buffer in each well. The plates were then placed in the FLIPR TETRA instrument and allowed to equilibrate at 37° C. AGN-211377 was added in a 25 μl volume to each well to give final concentrations of 0.1 μM, 0.3 μM, 1 μM, 3 μM, 10 μM, and 30 μM; or 0.067 μM, 0.1 μM, 0.2 μM, 0.3 μM, 0.67 μM, and 1 μM for cells over-expressing TP receptors. After 4.5 minutes, a 7-point serial dilution of the standard agonist for the corresponding receptor, in a 25 μl volume was injected at the final concentrations from 10^−11M to 10^−5M in 10-fold serial dilution increments for cells expressing human recombinant DP1, EP1, EP2, EP3, EP4, FP, and IP receptors. The dose range for the standard agonist for human recombinant TP receptors was from 10^−12M to 10^−6M. HBSS-HEPES buffer was used as the negative control for the standard agonists. Cells were excited with LED (light emitting diode) excitation at 470-495 nm and emission was measured through an emission filter at 515-575 nm. Assay plates were read for 3.5 minutes using the FLIPRTETRA.

Effective concentration which increases intracellular c-AMP production in mouse Prostanoid EP4 receptorEffective concentration which increases intracellular c-AMP production in mouse Prostanoid EP4 receptor

Cell Based Assay: Ca2+ signaling studies were performed using a FLIPR TETRA system (Molecular Devices, Sunnyvale, Calif., USA) in the 384-format. This is a high-throughput instrument for cell-based assays to monitor Ca2+ signaling associated with GPCRs and ion channels. Cells were seeded at a density of 5×104 cells/well in BioCoat poly-D-lysine coated, black wall, clear bottom 384-well plates (BD Biosciences, Franklin lakes, NJ, USA) and allowed to attach overnight in an incubator at 37° C. The cells were then washed twice with HBSS-HEPES buffer (Hanks' balanced salt solution without bicarbonate and phenol red, 20 mM HEPES, pH 7.4) using an ELx405 Select CW Microplate Washer (BioTek, Winooski, Vt., USA). After 60 min of dye-loading in the dark using the Ca2+-sensitive dye Fluo-4AM (Invitrogen, Carlsbad, Calif., USA), at a final concentration of 2×10^−6M, the plates were washed 4 times with HBSS-HEPES buffer to remove excess dye and leaving 50 μl of buffer in each well. The plates were then placed in the FLIPR TETRA instrument and allowed to equilibrate at 37° C. AGN-211377 was added in a 25 μl volume to each well to give final concentrations of 0.1 μM, 0.3 μM, 1 μM, 3 μM, 10 μM, and 30 μM; or 0.067 μM, 0.1 μM, 0.2 μM, 0.3 μM, 0.67 μM, and 1 μM for cells over-expressing TP receptors. After 4.5 minutes, a 7-point serial dilution of the standard agonist for the corresponding receptor, in a 25 μl volume was injected at the final concentrations from 10^−11M to 10^−5M in 10-fold serial dilution increments for cells expressing human recombinant DP1, EP1, EP2, EP3, EP4, FP, and IP receptors. The dose range for the standard agonist for human recombinant TP receptors was from 10^−12M to 10^−6M. HBSS-HEPES buffer was used as the negative control for the standard agonists. Cells were excited with LED (light emitting diode) excitation at 470-495 nm and emission was measured through an emission filter at 515-575 nm. Assay plates were read for 3.5 minutes using the FLIPRTETRA.Cell Based Assay: Ca2+ signaling studies were performed using a FLIPR TETRA system (Molecular Devices, Sunnyvale, Calif., USA) in the 384-format. This is a high-throughput instrument for cell-based assays to monitor Ca2+ signaling associated with GPCRs and ion channels. Cells were seeded at a density of 5×104 cells/well in BioCoat poly-D-lysine coated, black wall, clear bottom 384-well plates (BD Biosciences, Franklin lakes, NJ, USA) and allowed to attach overnight in an incubator at 37° C. The cells were then washed twice with HBSS-HEPES buffer (Hanks' balanced salt solution without bicarbonate and phenol red, 20 mM HEPES, pH 7.4) using an ELx405 Select CW Microplate Washer (BioTek, Winooski, Vt., USA). After 60 min of dye-loading in the dark using the Ca2+-sensitive dye Fluo-4AM (Invitrogen, Carlsbad, Calif., USA), at a final concentration of 2×10^−6M, the plates were washed 4 times with HBSS-HEPES buffer to remove excess dye and leaving 50 μl of buffer in each well. The plates were then placed in the FLIPR TETRA instrument and allowed to equilibrate at 37° C. AGN-211377 was added in a 25 μl volume to each well to give final concentrations of 0.1 μM, 0.3 μM, 1 μM, 3 μM, 10 μM, and 30 μM; or 0.067 μM, 0.1 μM, 0.2 μM, 0.3 μM, 0.67 μM, and 1 μM for cells over-expressing TP receptors. After 4.5 minutes, a 7-point serial dilution of the standard agonist for the corresponding receptor, in a 25 μl volume was injected at the final concentrations from 10^−11M to 10^−5M in 10-fold serial dilution increments for cells expressing human recombinant DP1, EP1, EP2, EP3, EP4, FP, and IP receptors. The dose range for the standard agonist for human recombinant TP receptors was from 10^−12M to 10^−6M. HBSS-HEPES buffer was used as the negative control for the standard agonists. Cells were excited with LED (light emitting diode) excitation at 470-495 nm and emission was measured through an emission filter at 515-575 nm. Assay plates were read for 3.5 minutes using the FLIPRTETRA.

Radioligand Binding: HEK-293 cells stably expressing the human or feline FP receptor, or EP1, EP2, EP3, or EP4 receptors were washed with TME buffer, scraped from the bottom of the flasks, and homogenized for 30 sec using a Brinkman PT 10/35 polytron. TME buffer was added to achieve a final 40 ml volume in the centrifuge tubes (the composition of TME is 100 mM TRIS base, 20 mM MgCl2, 2M EDTA; 10 N HCl is added to achieve a pH of 7.4).The cell homogenate was centrifuged at 19000 r.p.m. for 20 min at 4 C. using a Beckman Ti-60 rotor. The resultant pellet was resuspended in TME buffer to give a final 1 mg/ml protein concentration, as determined by Biorad assay. Radioligand binding competition assays vs. [3H-]17-phenyl PGF2 (5 nM) were performed in a 100 ul volume for 60 min. Binding reactions were started by adding plasma membrane fraction. The reaction was terminated by the addition of 4 ml ice-cold TRIS-HCl buffer and rapid filtration through glass fiber GF/B filters using a Brandel cell.Radioligand Binding: HEK-293 cells stably expressing the human or feline FP receptor, or EP1, EP2, EP3, or EP4 receptors were washed with TME buffer, scraped from the bottom of the flasks, and homogenized for 30 sec using a Brinkman PT 10/35 polytron. TME buffer was added to achieve a final 40 ml volume in the centrifuge tubes (the composition of TME is 100 mM TRIS base, 20 mM MgCl2, 2M EDTA; 10 N HCl is added to achieve a pH of 7.4).The cell homogenate was centrifuged at 19000 r.p.m. for 20 min at 4 C. using a Beckman Ti-60 rotor. The resultant pellet was resuspended in TME buffer to give a final 1 mg/ml protein concentration, as determined by Biorad assay. Radioligand binding competition assays vs. [3H-]17-phenyl PGF2 (5 nM) were performed in a 100 ul volume for 60 min. Binding reactions were started by adding plasma membrane fraction. The reaction was terminated by the addition of 4 ml ice-cold TRIS-HCl buffer and rapid filtration through glass fiber GF/B filters using a Brandel cell.

cAMP Assay: A 384-well drug plate was prepared to contain test compounds, PGE2 and cAMP in 16 serial dilutions in triplicate, using a Biomek station. HEK-EBNA cells expressing a target PG receptor subtype (EP2 or EP4) were suspended in a stimulation buffer (HBSS, 0.1% BSA, 0.5 mM IBMX and 5 mM HEPES, pH 7.4) in a density of 104 cells/5 μl. The reaction was initiated by mixing 5 μL drug dilutions with 5 μl of HEK-EBNA cells in a well, carried out for 30 min at room temperature, and followed by the addition of 5 μl anti-cAMP acceptor beads in the control buffer with Tween-20 (25 mM NaCl, 0.03% Tween-20, 5 mM HEPES, pH7.4). After 30 min in the dark at room temperature, the mixtures were incubated with 15 μl biotinylated-cAMP/strpavidin donor beads in Lysis/Detection buffer (0.1% BSA, 0.3% Tween-20 and 5 mM HEPES, pH7.4) for 45 min at the room temperature. Fluorescence changes were read using a Fusion-alpha HT microplate reader.cAMP Assay: A 384-well drug plate was prepared to contain test compounds, PGE2 and cAMP in 16 serial dilutions in triplicate, using a Biomek station. HEK-EBNA cells expressing a target PG receptor subtype (EP2 or EP4) were suspended in a stimulation buffer (HBSS, 0.1% BSA, 0.5 mM IBMX and 5 mM HEPES, pH 7.4) in a density of 104 cells/5 μl. The reaction was initiated by mixing 5 μL drug dilutions with 5 μl of HEK-EBNA cells in a well, carried out for 30 min at room temperature, and followed by the addition of 5 μl anti-cAMP acceptor beads in the control buffer with Tween-20 (25 mM NaCl, 0.03% Tween-20, 5 mM HEPES, pH7.4). After 30 min in the dark at room temperature, the mixtures were incubated with 15 μl biotinylated-cAMP/strpavidin donor beads in Lysis/Detection buffer (0.1% BSA, 0.3% Tween-20 and 5 mM HEPES, pH7.4) for 45 min at the room temperature. Fluorescence changes were read using a Fusion-alpha HT microplate reader.

Partial agonist activity at human EP4 receptor expressed in HEK293-AEQ17 cells assessed as cAMP accumulation by aequorin luminescence assayPartial agonist activity at human EP4 receptor expressed in HEK293-AEQ17 cells assessed as cAMP accumulation by aequorin luminescence assay

Partial agonist activity at human EP4 receptor expressed in HEK293-AEQ17 cells assessed as cAMP accumulation by aequorin luminescence assayPartial agonist activity at human EP4 receptor expressed in HEK293-AEQ17 cells assessed as cAMP accumulation by aequorin luminescence assay

Agonist activity at EP4 receptor expressed in HEK293 cells assessed as cAMP accumulationAgonist activity at EP4 receptor expressed in HEK293 cells assessed as cAMP accumulation

cAMP Assay: A 384-well drug plate was prepared to contain test compounds, PGE2 and cAMP in 16 serial dilutions in triplicate, using a Biomek station. HEK-EBNA cells expressing a target PG receptor subtype (EP2 or EP4) were suspended in a stimulation buffer (HBSS, 0.1% BSA, 0.5 mM IBMX and 5 mM HEPES, pH 7.4) in a density of 104 cells/5 μl. The reaction was initiated by mixing 5 μL drug dilutions with 5 μl of HEK-EBNA cells in a well, carried out for 30 min at room temperature, and followed by the addition of 5 μl anti-cAMP acceptor beads in the control buffer with Tween-20 (25 mM NaCl, 0.03% Tween-20, 5 mM HEPES, pH7.4). After 30 min in the dark at room temperature, the mixtures were incubated with 15 μl biotinylated-cAMP/strpavidin donor beads in Lysis/Detection buffer (0.1% BSA, 0.3% Tween-20 and 5 mM HEPES, pH7.4) for 45 min at the room temperature. Fluorescence changes were read using a Fusion-alpha HT microplate reader.cAMP Assay: A 384-well drug plate was prepared to contain test compounds, PGE2 and cAMP in 16 serial dilutions in triplicate, using a Biomek station. HEK-EBNA cells expressing a target PG receptor subtype (EP2 or EP4) were suspended in a stimulation buffer (HBSS, 0.1% BSA, 0.5 mM IBMX and 5 mM HEPES, pH 7.4) in a density of 104 cells/5 μl. The reaction was initiated by mixing 5 μL drug dilutions with 5 μl of HEK-EBNA cells in a well, carried out for 30 min at room temperature, and followed by the addition of 5 μl anti-cAMP acceptor beads in the control buffer with Tween-20 (25 mM NaCl, 0.03% Tween-20, 5 mM HEPES, pH7.4). After 30 min in the dark at room temperature, the mixtures were incubated with 15 μl biotinylated-cAMP/strpavidin donor beads in Lysis/Detection buffer (0.1% BSA, 0.3% Tween-20 and 5 mM HEPES, pH7.4) for 45 min at the room temperature. Fluorescence changes were read using a Fusion-alpha HT microplate reader.

Agonist activity at human EP4 receptorAgonist activity at human EP4 receptor

Agonist activity at rat EP4 receptor expressed in CHO cells assessed as cAMP production after 10 mins by radioimmunoassayAgonist activity at rat EP4 receptor expressed in CHO cells assessed as cAMP production after 10 mins by radioimmunoassay

Effective concentration which increases intracellular c-AMP production in mouse Prostanoid EP4 receptorEffective concentration which increases intracellular c-AMP production in mouse Prostanoid EP4 receptor

Agonist activity at rat EP4 receptor expressed in CHO cells assessed as cAMP production after 10 mins by radioimmunoassayAgonist activity at rat EP4 receptor expressed in CHO cells assessed as cAMP production after 10 mins by radioimmunoassay

Effective concentration which increases intracellular c-AMP production in mouse Prostanoid EP4 receptorEffective concentration which increases intracellular c-AMP production in mouse Prostanoid EP4 receptor

Agonist activity at human EP4 receptor expressed in HEK293 cells by calcium-5 dye based FLIPR assayAgonist activity at human EP4 receptor expressed in HEK293 cells by calcium-5 dye based FLIPR assay

Agonist activity at rat EP4 receptor expressed in CHO cells assessed as cAMP production after 10 mins by radioimmunoassayAgonist activity at rat EP4 receptor expressed in CHO cells assessed as cAMP production after 10 mins by radioimmunoassay

Activity at rat EP4 transfected in HEK293 cells by cAMP accumulationActivity at rat EP4 transfected in HEK293 cells by cAMP accumulation

Agonist activity against recombinant prostanoid EP4 receptor stably transfected in CHO cellsAgonist activity against recombinant prostanoid EP4 receptor stably transfected in CHO cells

Agonist activity against recombinant prostanoid EP4 receptor stably transfected in CHO cellsAgonist activity against recombinant prostanoid EP4 receptor stably transfected in CHO cells

Effective concentration which increases intracellular c-AMP production in mouse Prostanoid EP4 receptorEffective concentration which increases intracellular c-AMP production in mouse Prostanoid EP4 receptor

Agonist activity against recombinant prostanoid EP4 receptor stably transfected in CHO cellsAgonist activity against recombinant prostanoid EP4 receptor stably transfected in CHO cells

Activity at rat EP4 transfected in HEK293 cells by cAMP accumulationActivity at rat EP4 transfected in HEK293 cells by cAMP accumulation

Effective concentration for increased intracellular c-AMP production by mouse Prostanoid EP4 receptorEffective concentration for increased intracellular c-AMP production by mouse Prostanoid EP4 receptor

Effective concentration required for prostanoid EP4 receptor activity was determinedEffective concentration required for prostanoid EP4 receptor activity was determined

Effective concentration required for prostanoid EP4 receptor activity was determinedEffective concentration required for prostanoid EP4 receptor activity was determined

Effective concentration which increases intracellular c-AMP production in mouse Prostanoid EP4 receptorEffective concentration which increases intracellular c-AMP production in mouse Prostanoid EP4 receptor

Activity at rat EP4 transfected in HEK293 cells by cAMP accumulationActivity at rat EP4 transfected in HEK293 cells by cAMP accumulation

Agonist activity at rat EP4 receptor expressed in CHO cells assessed as cAMP production after 10 mins by radioimmunoassayAgonist activity at rat EP4 receptor expressed in CHO cells assessed as cAMP production after 10 mins by radioimmunoassay

Agonist activity at rat EP4 receptor expressed in CHO cells assessed as cAMP production after 10 mins by radioimmunoassayAgonist activity at rat EP4 receptor expressed in CHO cells assessed as cAMP production after 10 mins by radioimmunoassay

Effective concentration for increased intracellular c-AMP production by mouse Prostanoid EP4 receptorEffective concentration for increased intracellular c-AMP production by mouse Prostanoid EP4 receptor

Agonist activity against recombinant prostanoid EP4 receptor stably transfected in CHO cellsAgonist activity against recombinant prostanoid EP4 receptor stably transfected in CHO cells

Agonist activity at human EP4 receptor expressed in CHO cells assessed as increase in intracellular cAMP level after 30 mins by HTRF methodAgonist activity at human EP4 receptor expressed in CHO cells assessed as increase in intracellular cAMP level after 30 mins by HTRF method

Agonist activity at human EP4 receptorAgonist activity at human EP4 receptor

Agonist activity at human EP4 receptorAgonist activity at human EP4 receptor

Agonist activity at rat EP4 receptorAgonist activity at rat EP4 receptor

Agonist activity at rat EP4 receptor expressed in CHO cells assessed as cAMP production after 10 mins by radioimmunoassayAgonist activity at rat EP4 receptor expressed in CHO cells assessed as cAMP production after 10 mins by radioimmunoassay

Agonist activity at human prostaglandin EP4 receptorAgonist activity at human prostaglandin EP4 receptor

Partial agonist activity at human EP4 receptor expressed in HEK293-AEQ17 cells assessed as cAMP accumulation by aequorin luminescence assayPartial agonist activity at human EP4 receptor expressed in HEK293-AEQ17 cells assessed as cAMP accumulation by aequorin luminescence assay

Partial agonist activity at human EP4 receptor expressed in HEK293-AEQ17 cells assessed as cAMP accumulation by aequorin luminescence assayPartial agonist activity at human EP4 receptor expressed in HEK293-AEQ17 cells assessed as cAMP accumulation by aequorin luminescence assay

cAMP Assay: 1. Seed cells on an EP2 or EP4 STEP plate at a density of 40,000-80,000 cells/well in 200 uL of reduced serum medium containing 0.5% FBS. Place the plate in a 37° C. incubator with 5% CO2 and incubate overnight. 2. After 16-18 hours of incubation, aspirate the culture media from each well. 3. Add 200 ul of culture medium containing 500 uM IBMX (an inhibitor of cAMP phosphodiesterase) and different concentration of test compounds to the assigned wells. For each test compound, at least 8 concentrations starting at highest 10 M and lowest 0.01 pM were tested. In addition each concentration had triplicates. A PGE2 curve (concentrations from lowest to highest, 0 pM, 0.384 pM, 1.92 pM, 9.6 pM, 48 pM, 240 pM, 1200 pM, and 6000 pM) was always run in parallel with test compounds. 4. Incubate the cells in a cell culture incubator for 30 minutes. 5. Centrifuge the plate at 1,000x rpm for 10 minutes. 6. Aspirate the supernatant.cAMP Assay: 1. Seed cells on an EP2 or EP4 STEP plate at a density of 40,000-80,000 cells/well in 200 uL of reduced serum medium containing 0.5% FBS. Place the plate in a 37° C. incubator with 5% CO2 and incubate overnight. 2. After 16-18 hours of incubation, aspirate the culture media from each well. 3. Add 200 ul of culture medium containing 500 uM IBMX (an inhibitor of cAMP phosphodiesterase) and different concentration of test compounds to the assigned wells. For each test compound, at least 8 concentrations starting at highest 10 M and lowest 0.01 pM were tested. In addition each concentration had triplicates. A PGE2 curve (concentrations from lowest to highest, 0 pM, 0.384 pM, 1.92 pM, 9.6 pM, 48 pM, 240 pM, 1200 pM, and 6000 pM) was always run in parallel with test compounds. 4. Incubate the cells in a cell culture incubator for 30 minutes. 5. Centrifuge the plate at 1,000x rpm for 10 minutes. 6. Aspirate the supernatant.

Agonist activity at rat EP4 receptor expressed in CHO cells assessed as cAMP production after 10 mins by radioimmunoassayAgonist activity at rat EP4 receptor expressed in CHO cells assessed as cAMP production after 10 mins by radioimmunoassay

cAMP Assay: 1. Seed cells on an EP2 or EP4 STEP plate at a density of 40,000-80,000 cells/well in 200 uL of reduced serum medium containing 0.5% FBS. Place the plate in a 37° C. incubator with 5% CO2 and incubate overnight. 2. After 16-18 hours of incubation, aspirate the culture media from each well. 3. Add 200 ul of culture medium containing 500 uM IBMX (an inhibitor of cAMP phosphodiesterase) and different concentration of test compounds to the assigned wells. For each test compound, at least 8 concentrations starting at highest 10 M and lowest 0.01 pM were tested. In addition each concentration had triplicates. A PGE2 curve (concentrations from lowest to highest, 0 pM, 0.384 pM, 1.92 pM, 9.6 pM, 48 pM, 240 pM, 1200 pM, and 6000 pM) was always run in parallel with test compounds. 4. Incubate the cells in a cell culture incubator for 30 minutes. 5. Centrifuge the plate at 1,000x rpm for 10 minutes. 6. Aspirate the supernatant.cAMP Assay: 1. Seed cells on an EP2 or EP4 STEP plate at a density of 40,000-80,000 cells/well in 200 uL of reduced serum medium containing 0.5% FBS. Place the plate in a 37° C. incubator with 5% CO2 and incubate overnight. 2. After 16-18 hours of incubation, aspirate the culture media from each well. 3. Add 200 ul of culture medium containing 500 uM IBMX (an inhibitor of cAMP phosphodiesterase) and different concentration of test compounds to the assigned wells. For each test compound, at least 8 concentrations starting at highest 10 M and lowest 0.01 pM were tested. In addition each concentration had triplicates. A PGE2 curve (concentrations from lowest to highest, 0 pM, 0.384 pM, 1.92 pM, 9.6 pM, 48 pM, 240 pM, 1200 pM, and 6000 pM) was always run in parallel with test compounds. 4. Incubate the cells in a cell culture incubator for 30 minutes. 5. Centrifuge the plate at 1,000x rpm for 10 minutes. 6. Aspirate the supernatant.

Agonist activity at rabbit EP4 receptor assessed as relaxation of Kcl-induced tissue contraction by isometric transducer methodAgonist activity at rabbit EP4 receptor assessed as relaxation of Kcl-induced tissue contraction by isometric transducer method

Agonist activity at rat EP4 receptor expressed in CHO cells assessed as cAMP production after 10 mins by radioimmunoassayAgonist activity at rat EP4 receptor expressed in CHO cells assessed as cAMP production after 10 mins by radioimmunoassay

Agonist activity at rat EP4 receptor expressed in CHO cells assessed as cAMP production after 10 mins by radioimmunoassayAgonist activity at rat EP4 receptor expressed in CHO cells assessed as cAMP production after 10 mins by radioimmunoassay

Functional activity at human EP4 receptorFunctional activity at human EP4 receptor

Activity at rat EP4 transfected in HEK293 cells by cAMP accumulationActivity at rat EP4 transfected in HEK293 cells by cAMP accumulation

Agonist activity against recombinant prostanoid EP4 receptor stably transfected in CHO cellsAgonist activity against recombinant prostanoid EP4 receptor stably transfected in CHO cells

Partial agonist activity at human EP4 receptor expressed in HEK293-AEQ17 cells assessed as cAMP accumulation by aequorin luminescence assayPartial agonist activity at human EP4 receptor expressed in HEK293-AEQ17 cells assessed as cAMP accumulation by aequorin luminescence assay

cAMP Assay: 1. Seed cells on an EP2 or EP4 STEP plate at a density of 40,000-80,000 cells/well in 200 uL of reduced serum medium containing 0.5% FBS. Place the plate in a 37° C. incubator with 5% CO2 and incubate overnight. 2. After 16-18 hours of incubation, aspirate the culture media from each well. 3. Add 200 ul of culture medium containing 500 uM IBMX (an inhibitor of cAMP phosphodiesterase) and different concentration of test compounds to the assigned wells. For each test compound, at least 8 concentrations starting at highest 10 M and lowest 0.01 pM were tested. In addition each concentration had triplicates. A PGE2 curve (concentrations from lowest to highest, 0 pM, 0.384 pM, 1.92 pM, 9.6 pM, 48 pM, 240 pM, 1200 pM, and 6000 pM) was always run in parallel with test compounds. 4. Incubate the cells in a cell culture incubator for 30 minutes. 5. Centrifuge the plate at 1,000x rpm for 10 minutes. 6. Aspirate the supernatant.cAMP Assay: 1. Seed cells on an EP2 or EP4 STEP plate at a density of 40,000-80,000 cells/well in 200 uL of reduced serum medium containing 0.5% FBS. Place the plate in a 37° C. incubator with 5% CO2 and incubate overnight. 2. After 16-18 hours of incubation, aspirate the culture media from each well. 3. Add 200 ul of culture medium containing 500 uM IBMX (an inhibitor of cAMP phosphodiesterase) and different concentration of test compounds to the assigned wells. For each test compound, at least 8 concentrations starting at highest 10 M and lowest 0.01 pM were tested. In addition each concentration had triplicates. A PGE2 curve (concentrations from lowest to highest, 0 pM, 0.384 pM, 1.92 pM, 9.6 pM, 48 pM, 240 pM, 1200 pM, and 6000 pM) was always run in parallel with test compounds. 4. Incubate the cells in a cell culture incubator for 30 minutes. 5. Centrifuge the plate at 1,000x rpm for 10 minutes. 6. Aspirate the supernatant.

Activity at rat EP4 transfected in HEK293 cells by cAMP accumulationActivity at rat EP4 transfected in HEK293 cells by cAMP accumulation

Agonist activity against recombinant prostanoid EP4 receptor stably transfected in CHO cellsAgonist activity against recombinant prostanoid EP4 receptor stably transfected in CHO cells

Radioligand Binding: HEK-293 cells stably expressing the human or feline FP receptor, or EP1, EP2, EP3, or EP4 receptors were washed with TME buffer, scraped from the bottom of the flasks, and homogenized for 30 sec using a Brinkman PT 10/35 polytron. TME buffer was added to achieve a final 40 ml volume in the centrifuge tubes (the composition of TME is 100 mM TRIS base, 20 mM MgCl2, 2M EDTA; 10 N HCl is added to achieve a pH of 7.4).The cell homogenate was centrifuged at 19000 r.p.m. for 20 min at 4 C. using a Beckman Ti-60 rotor. The resultant pellet was resuspended in TME buffer to give a final 1 mg/ml protein concentration, as determined by Biorad assay. Radioligand binding competition assays vs. [3H-]17-phenyl PGF2 (5 nM) were performed in a 100 ul volume for 60 min. Binding reactions were started by adding plasma membrane fraction. The reaction was terminated by the addition of 4 ml ice-cold TRIS-HCl buffer and rapid filtration through glass fiber GF/B filters using a Brandel cell.Radioligand Binding: HEK-293 cells stably expressing the human or feline FP receptor, or EP1, EP2, EP3, or EP4 receptors were washed with TME buffer, scraped from the bottom of the flasks, and homogenized for 30 sec using a Brinkman PT 10/35 polytron. TME buffer was added to achieve a final 40 ml volume in the centrifuge tubes (the composition of TME is 100 mM TRIS base, 20 mM MgCl2, 2M EDTA; 10 N HCl is added to achieve a pH of 7.4).The cell homogenate was centrifuged at 19000 r.p.m. for 20 min at 4 C. using a Beckman Ti-60 rotor. The resultant pellet was resuspended in TME buffer to give a final 1 mg/ml protein concentration, as determined by Biorad assay. Radioligand binding competition assays vs. [3H-]17-phenyl PGF2 (5 nM) were performed in a 100 ul volume for 60 min. Binding reactions were started by adding plasma membrane fraction. The reaction was terminated by the addition of 4 ml ice-cold TRIS-HCl buffer and rapid filtration through glass fiber GF/B filters using a Brandel cell.

Agonist activity at rat EP4 receptor expressed in CHO cells assessed as cAMP production after 10 mins by radioimmunoassayAgonist activity at rat EP4 receptor expressed in CHO cells assessed as cAMP production after 10 mins by radioimmunoassay

Radioligand Binding: HEK-293 cells stably expressing the human or feline FP receptor, or EP1, EP2, or EP4 receptors were washed with TME buffer, scraped from the bottom of the flasks, and homogenized for 30 sec using a Brinkman PT 10/35 polytron. TME buffer was added to achieve a final 40 ml volume in the centrifuge tubes (the composition of TME is 100 mM TRIS base, 20 mM MgCl2, 2M EDTA; 10N HCl is added to achieve a pH of 7.4). The cell homogenate was centrifuged at 19000 r.p.m. for 20 min at 4 °C. using a Beckman Ti-60 rotor. The resultant pellet was resuspended in TME buffer to give a final 1 mg/ml protein concentration, as determined by Biorad assay. Radioligand binding competition assays vs. [3H-]17-phenyl PGF2a (5 nM) were performed in a 100 μl volume for 60 min. Binding reactions were started by adding plasma membrane fraction. The reaction was terminated by the addition of 4 ml ice-cold TRIS-HCl buffer and rapid filtration through glass fiber GF/B filters using a Brandel cell harvester. The filters were washed 3 times with ice-cold buffer and oven dried for one hour. [3H−] PGE2 (specific activity 180 Ci mmol) was used as the radioligand for EP receptors. [3H] 17-phenyl PGF2a was employed for FP receptor binding studies. Binding studies employing EP1, EP2, EP4 and FP receptors were performed in duplicate in at least three separate experiments. A 200 μl assay volume was used. Incubations were for 60 min at 25 °C. and were terminated by the addition of 4 ml of ice-cold 50 mM TRIS-HCl, followed by rapid filtration through Whatman GF/B filters and three additional 4 ml washes in a cell harvester (Brandel). Competition studies were performed using a final concentration of 5 nM [3H]-PGE2, or 5 nM [3H] 17-phenyl PGF2a and non-specific binding determined with 10^−5M of unlabeled PGE2, or 17-phenyl PGF2a, according to receptor subtype studied.Radioligand Binding: HEK-293 cells stably expressing the human or feline FP receptor, or EP1, EP2, or EP4 receptors were washed with TME buffer, scraped from the bottom of the flasks, and homogenized for 30 sec using a Brinkman PT 10/35 polytron. TME buffer was added to achieve a final 40 ml volume in the centrifuge tubes (the composition of TME is 100 mM TRIS base, 20 mM MgCl2, 2M EDTA; 10N HCl is added to achieve a pH of 7.4). The cell homogenate was centrifuged at 19000 r.p.m. for 20 min at 4 °C. using a Beckman Ti-60 rotor. The resultant pellet was resuspended in TME buffer to give a final 1 mg/ml protein concentration, as determined by Biorad assay. Radioligand binding competition assays vs. [3H-]17-phenyl PGF2a (5 nM) were performed in a 100 μl volume for 60 min. Binding reactions were started by adding plasma membrane fraction. The reaction was terminated by the addition of 4 ml ice-cold TRIS-HCl buffer and rapid filtration through glass fiber GF/B filters using a Brandel cell harvester. The filters were washed 3 times with ice-cold buffer and oven dried for one hour. [3H−] PGE2 (specific activity 180 Ci mmol) was used as the radioligand for EP receptors. [3H] 17-phenyl PGF2a was employed for FP receptor binding studies. Binding studies employing EP1, EP2, EP4 and FP receptors were performed in duplicate in at least three separate experiments. A 200 μl assay volume was used. Incubations were for 60 min at 25 °C. and were terminated by the addition of 4 ml of ice-cold 50 mM TRIS-HCl, followed by rapid filtration through Whatman GF/B filters and three additional 4 ml washes in a cell harvester (Brandel). Competition studies were performed using a final concentration of 5 nM [3H]-PGE2, or 5 nM [3H] 17-phenyl PGF2a and non-specific binding determined with 10^−5M of unlabeled PGE2, or 17-phenyl PGF2a, according to receptor subtype studied.

Agonist activity at human EP4 receptor expressed in HEK293 cells by calcium-5 dye based FLIPR assayAgonist activity at human EP4 receptor expressed in HEK293 cells by calcium-5 dye based FLIPR assay

Agonist activity against recombinant prostanoid EP4 receptor stably transfected in CHO cellsAgonist activity against recombinant prostanoid EP4 receptor stably transfected in CHO cells

Functional activity at human EP4 receptorFunctional activity at human EP4 receptor

Agonist activity at recombinant human EP4 receptor expressed in CHO cells assessed as increase in intracellular cAMP level by EIAAgonist activity at recombinant human EP4 receptor expressed in CHO cells assessed as increase in intracellular cAMP level by EIA

Effective concentration which increases intracellular c-AMP production in mouse Prostanoid EP4 receptorEffective concentration which increases intracellular c-AMP production in mouse Prostanoid EP4 receptor

Agonist activity against recombinant prostanoid EP4 receptor stably transfected in CHO cellsAgonist activity against recombinant prostanoid EP4 receptor stably transfected in CHO cells

Agonist activity at rat EP4 receptor expressed in CHO cells assessed as cAMP production after 10 mins by radioimmunoassayAgonist activity at rat EP4 receptor expressed in CHO cells assessed as cAMP production after 10 mins by radioimmunoassay

Effective concentration required for prostanoid EP4 receptor activity was determinedEffective concentration required for prostanoid EP4 receptor activity was determined

Partial agonist activity at EP4 receptor in human whole blood assessed as inhibition of LPS-induced TNFalpha productionPartial agonist activity at EP4 receptor in human whole blood assessed as inhibition of LPS-induced TNFalpha production

Radioligand Binding: HEK-293 cells stably expressing the human or feline FP receptor, or EP1, EP2, EP3, or EP4 receptors were washed with TME buffer, scraped from the bottom of the flasks, and homogenized for 30 sec using a Brinkman PT 10/35 polytron. TME buffer was added to achieve a final 40 ml volume in the centrifuge tubes (the composition of TME is 100 mM TRIS base, 20 mM MgCl2, 2M EDTA; 10 N HCl is added to achieve a pH of 7.4).The cell homogenate was centrifuged at 19000 r.p.m. for 20 min at 4 C. using a Beckman Ti-60 rotor. The resultant pellet was resuspended in TME buffer to give a final 1 mg/ml protein concentration, as determined by Biorad assay. Radioligand binding competition assays vs. [3H-]17-phenyl PGF2 (5 nM) were performed in a 100 ul volume for 60 min. Binding reactions were started by adding plasma membrane fraction. The reaction was terminated by the addition of 4 ml ice-cold TRIS-HCl buffer and rapid filtration through glass fiber GF/B filters using a Brandel cell.Radioligand Binding: HEK-293 cells stably expressing the human or feline FP receptor, or EP1, EP2, EP3, or EP4 receptors were washed with TME buffer, scraped from the bottom of the flasks, and homogenized for 30 sec using a Brinkman PT 10/35 polytron. TME buffer was added to achieve a final 40 ml volume in the centrifuge tubes (the composition of TME is 100 mM TRIS base, 20 mM MgCl2, 2M EDTA; 10 N HCl is added to achieve a pH of 7.4).The cell homogenate was centrifuged at 19000 r.p.m. for 20 min at 4 C. using a Beckman Ti-60 rotor. The resultant pellet was resuspended in TME buffer to give a final 1 mg/ml protein concentration, as determined by Biorad assay. Radioligand binding competition assays vs. [3H-]17-phenyl PGF2 (5 nM) were performed in a 100 ul volume for 60 min. Binding reactions were started by adding plasma membrane fraction. The reaction was terminated by the addition of 4 ml ice-cold TRIS-HCl buffer and rapid filtration through glass fiber GF/B filters using a Brandel cell.

Agonist activity at human EP4 receptor expressed in HEK293 cells by calcium-5 dye based FLIPR assayAgonist activity at human EP4 receptor expressed in HEK293 cells by calcium-5 dye based FLIPR assay

Agonist activity against recombinant prostanoid EP4 receptor stably transfected in CHO cellsAgonist activity against recombinant prostanoid EP4 receptor stably transfected in CHO cells

cAMP Assay: 1. Seed cells on an EP2 or EP4 STEP plate at a density of 40,000-80,000 cells/well in 200 uL of reduced serum medium containing 0.5% FBS. Place the plate in a 37° C. incubator with 5% CO2 and incubate overnight. 2. After 16-18 hours of incubation, aspirate the culture media from each well. 3. Add 200 ul of culture medium containing 500 uM IBMX (an inhibitor of cAMP phosphodiesterase) and different concentration of test compounds to the assigned wells. For each test compound, at least 8 concentrations starting at highest 10 M and lowest 0.01 pM were tested. In addition each concentration had triplicates. A PGE2 curve (concentrations from lowest to highest, 0 pM, 0.384 pM, 1.92 pM, 9.6 pM, 48 pM, 240 pM, 1200 pM, and 6000 pM) was always run in parallel with test compounds. 4. Incubate the cells in a cell culture incubator for 30 minutes. 5. Centrifuge the plate at 1,000x rpm for 10 minutes. 6. Aspirate the supernatant.cAMP Assay: 1. Seed cells on an EP2 or EP4 STEP plate at a density of 40,000-80,000 cells/well in 200 uL of reduced serum medium containing 0.5% FBS. Place the plate in a 37° C. incubator with 5% CO2 and incubate overnight. 2. After 16-18 hours of incubation, aspirate the culture media from each well. 3. Add 200 ul of culture medium containing 500 uM IBMX (an inhibitor of cAMP phosphodiesterase) and different concentration of test compounds to the assigned wells. For each test compound, at least 8 concentrations starting at highest 10 M and lowest 0.01 pM were tested. In addition each concentration had triplicates. A PGE2 curve (concentrations from lowest to highest, 0 pM, 0.384 pM, 1.92 pM, 9.6 pM, 48 pM, 240 pM, 1200 pM, and 6000 pM) was always run in parallel with test compounds. 4. Incubate the cells in a cell culture incubator for 30 minutes. 5. Centrifuge the plate at 1,000x rpm for 10 minutes. 6. Aspirate the supernatant.

Radioligand Binding: HEK-293 cells stably expressing the human or feline FP receptor, or EP1, EP2, EP3, or EP4 receptors were washed with TME buffer, scraped from the bottom of the flasks, and homogenized for 30 sec using a Brinkman PT 10/35 polytron. TME buffer was added to achieve a final 40 ml volume in the centrifuge tubes (the composition of TME is 100 mM TRIS base, 20 mM MgCl2, 2M EDTA; 10 N HCl is added to achieve a pH of 7.4).The cell homogenate was centrifuged at 19000 r.p.m. for 20 min at 4 C. using a Beckman Ti-60 rotor. The resultant pellet was resuspended in TME buffer to give a final 1 mg/ml protein concentration, as determined by Biorad assay. Radioligand binding competition assays vs. [3H-]17-phenyl PGF2 (5 nM) were performed in a 100 ul volume for 60 min. Binding reactions were started by adding plasma membrane fraction. The reaction was terminated by the addition of 4 ml ice-cold TRIS-HCl buffer and rapid filtration through glass fiber GF/B filters using a Brandel cell.Radioligand Binding: HEK-293 cells stably expressing the human or feline FP receptor, or EP1, EP2, EP3, or EP4 receptors were washed with TME buffer, scraped from the bottom of the flasks, and homogenized for 30 sec using a Brinkman PT 10/35 polytron. TME buffer was added to achieve a final 40 ml volume in the centrifuge tubes (the composition of TME is 100 mM TRIS base, 20 mM MgCl2, 2M EDTA; 10 N HCl is added to achieve a pH of 7.4).The cell homogenate was centrifuged at 19000 r.p.m. for 20 min at 4 C. using a Beckman Ti-60 rotor. The resultant pellet was resuspended in TME buffer to give a final 1 mg/ml protein concentration, as determined by Biorad assay. Radioligand binding competition assays vs. [3H-]17-phenyl PGF2 (5 nM) were performed in a 100 ul volume for 60 min. Binding reactions were started by adding plasma membrane fraction. The reaction was terminated by the addition of 4 ml ice-cold TRIS-HCl buffer and rapid filtration through glass fiber GF/B filters using a Brandel cell.

Effective concentration required for prostanoid EP4 receptor activity was determinedEffective concentration required for prostanoid EP4 receptor activity was determined

Radioligand Binding: HEK-293 cells stably expressing the human or feline FP receptor, or EP1, EP2, EP3, or EP4 receptors were washed with TME buffer, scraped from the bottom of the flasks, and homogenized for 30 sec using a Brinkman PT 10/35 polytron. TME buffer was added to achieve a final 40 ml volume in the centrifuge tubes (the composition of TME is 100 mM TRIS base, 20 mM MgCl2, 2M EDTA; 10 N HCl is added to achieve a pH of 7.4).The cell homogenate was centrifuged at 19000 r.p.m. for 20 min at 4 C. using a Beckman Ti-60 rotor. The resultant pellet was resuspended in TME buffer to give a final 1 mg/ml protein concentration, as determined by Biorad assay. Radioligand binding competition assays vs. [3H-]17-phenyl PGF2 (5 nM) were performed in a 100 ul volume for 60 min. Binding reactions were started by adding plasma membrane fraction. The reaction was terminated by the addition of 4 ml ice-cold TRIS-HCl buffer and rapid filtration through glass fiber GF/B filters using a Brandel cell.Radioligand Binding: HEK-293 cells stably expressing the human or feline FP receptor, or EP1, EP2, EP3, or EP4 receptors were washed with TME buffer, scraped from the bottom of the flasks, and homogenized for 30 sec using a Brinkman PT 10/35 polytron. TME buffer was added to achieve a final 40 ml volume in the centrifuge tubes (the composition of TME is 100 mM TRIS base, 20 mM MgCl2, 2M EDTA; 10 N HCl is added to achieve a pH of 7.4).The cell homogenate was centrifuged at 19000 r.p.m. for 20 min at 4 C. using a Beckman Ti-60 rotor. The resultant pellet was resuspended in TME buffer to give a final 1 mg/ml protein concentration, as determined by Biorad assay. Radioligand binding competition assays vs. [3H-]17-phenyl PGF2 (5 nM) were performed in a 100 ul volume for 60 min. Binding reactions were started by adding plasma membrane fraction. The reaction was terminated by the addition of 4 ml ice-cold TRIS-HCl buffer and rapid filtration through glass fiber GF/B filters using a Brandel cell.

Agonist activity at human EP4 receptor expressed in HEK293 cells by calcium-5 dye based FLIPR assayAgonist activity at human EP4 receptor expressed in HEK293 cells by calcium-5 dye based FLIPR assay

Agonist activity at rat EP4 receptor expressed in CHO cells assessed as cAMP production after 10 mins by radioimmunoassayAgonist activity at rat EP4 receptor expressed in CHO cells assessed as cAMP production after 10 mins by radioimmunoassay

Cell Based Assay: Ca2+ signaling studies were performed using a FLIPR TETRA system (Molecular Devices, Sunnyvale, Calif., USA) in the 384-format. This is a high-throughput instrument for cell-based assays to monitor Ca2+ signaling associated with GPCRs and ion channels. Cells were seeded at a density of 5×104 cells/well in BioCoat poly-D-lysine coated, black wall, clear bottom 384-well plates (BD Biosciences, Franklin lakes, NJ, USA) and allowed to attach overnight in an incubator at 37° C. The cells were then washed twice with HBSS-HEPES buffer (Hanks' balanced salt solution without bicarbonate and phenol red, 20 mM HEPES, pH 7.4) using an ELx405 Select CW Microplate Washer (BioTek, Winooski, Vt., USA). After 60 min of dye-loading in the dark using the Ca2+-sensitive dye Fluo-4AM (Invitrogen, Carlsbad, Calif., USA), at a final concentration of 2×10^−6M, the plates were washed 4 times with HBSS-HEPES buffer to remove excess dye and leaving 50 μl of buffer in each well. The plates were then placed in the FLIPR TETRA instrument and allowed to equilibrate at 37° C. AGN-211377 was added in a 25 μl volume to each well to give final concentrations of 0.1 μM, 0.3 μM, 1 μM, 3 μM, 10 μM, and 30 μM; or 0.067 μM, 0.1 μM, 0.2 μM, 0.3 μM, 0.67 μM, and 1 μM for cells over-expressing TP receptors. After 4.5 minutes, a 7-point serial dilution of the standard agonist for the corresponding receptor, in a 25 μl volume was injected at the final concentrations from 10^−11M to 10^−5M in 10-fold serial dilution increments for cells expressing human recombinant DP1, EP1, EP2, EP3, EP4, FP, and IP receptors. The dose range for the standard agonist for human recombinant TP receptors was from 10^−12M to 10^−6M. HBSS-HEPES buffer was used as the negative control for the standard agonists. Cells were excited with LED (light emitting diode) excitation at 470-495 nm and emission was measured through an emission filter at 515-575 nm. Assay plates were read for 3.5 minutes using the FLIPRTETRA.Cell Based Assay: Ca2+ signaling studies were performed using a FLIPR TETRA system (Molecular Devices, Sunnyvale, Calif., USA) in the 384-format. This is a high-throughput instrument for cell-based assays to monitor Ca2+ signaling associated with GPCRs and ion channels. Cells were seeded at a density of 5×104 cells/well in BioCoat poly-D-lysine coated, black wall, clear bottom 384-well plates (BD Biosciences, Franklin lakes, NJ, USA) and allowed to attach overnight in an incubator at 37° C. The cells were then washed twice with HBSS-HEPES buffer (Hanks' balanced salt solution without bicarbonate and phenol red, 20 mM HEPES, pH 7.4) using an ELx405 Select CW Microplate Washer (BioTek, Winooski, Vt., USA). After 60 min of dye-loading in the dark using the Ca2+-sensitive dye Fluo-4AM (Invitrogen, Carlsbad, Calif., USA), at a final concentration of 2×10^−6M, the plates were washed 4 times with HBSS-HEPES buffer to remove excess dye and leaving 50 μl of buffer in each well. The plates were then placed in the FLIPR TETRA instrument and allowed to equilibrate at 37° C. AGN-211377 was added in a 25 μl volume to each well to give final concentrations of 0.1 μM, 0.3 μM, 1 μM, 3 μM, 10 μM, and 30 μM; or 0.067 μM, 0.1 μM, 0.2 μM, 0.3 μM, 0.67 μM, and 1 μM for cells over-expressing TP receptors. After 4.5 minutes, a 7-point serial dilution of the standard agonist for the corresponding receptor, in a 25 μl volume was injected at the final concentrations from 10^−11M to 10^−5M in 10-fold serial dilution increments for cells expressing human recombinant DP1, EP1, EP2, EP3, EP4, FP, and IP receptors. The dose range for the standard agonist for human recombinant TP receptors was from 10^−12M to 10^−6M. HBSS-HEPES buffer was used as the negative control for the standard agonists. Cells were excited with LED (light emitting diode) excitation at 470-495 nm and emission was measured through an emission filter at 515-575 nm. Assay plates were read for 3.5 minutes using the FLIPRTETRA.

Agonist activity at rat EP4 receptor expressed in CHO cells assessed as cAMP production after 10 mins by radioimmunoassayAgonist activity at rat EP4 receptor expressed in CHO cells assessed as cAMP production after 10 mins by radioimmunoassay

Agonist activity at human EP4 receptor expressed in CHO cells assessed as increase in intracellular cAMP level after 30 mins by HTRF methodAgonist activity at human EP4 receptor expressed in CHO cells assessed as increase in intracellular cAMP level after 30 mins by HTRF method

Agonist activity at rat EP4 receptor expressed in CHO cells assessed as cAMP production after 10 mins by radioimmunoassayAgonist activity at rat EP4 receptor expressed in CHO cells assessed as cAMP production after 10 mins by radioimmunoassay

Agonist activity at rat EP4 receptor expressed in CHO cells assessed as cAMP production after 10 mins by radioimmunoassayAgonist activity at rat EP4 receptor expressed in CHO cells assessed as cAMP production after 10 mins by radioimmunoassay

Effective concentration which increases intracellular c-AMP production in mouse Prostanoid EP4 receptorEffective concentration which increases intracellular c-AMP production in mouse Prostanoid EP4 receptor

Partial agonist activity at human EP4 receptor expressed in HEK293-AEQ17 cells assessed as cAMP accumulation by aequorin luminescence assayPartial agonist activity at human EP4 receptor expressed in HEK293-AEQ17 cells assessed as cAMP accumulation by aequorin luminescence assay

Agonist activity at human EP4 receptorAgonist activity at human EP4 receptor

cAMP Assay: A 384-well drug plate was prepared to contain test compounds, PGE2 and cAMP in 16 serial dilutions in triplicate, using a Biomek station. HEK-EBNA cells expressing a target PG receptor subtype (EP2 or EP4) were suspended in a stimulation buffer (HBSS, 0.1% BSA, 0.5 mM IBMX and 5 mM HEPES, pH 7.4) in a density of 104 cells/5 μl. The reaction was initiated by mixing 5 μL drug dilutions with 5 μl of HEK-EBNA cells in a well, carried out for 30 min at room temperature, and followed by the addition of 5 μl anti-cAMP acceptor beads in the control buffer with Tween-20 (25 mM NaCl, 0.03% Tween-20, 5 mM HEPES, pH7.4). After 30 min in the dark at room temperature, the mixtures were incubated with 15 μl biotinylated-cAMP/strpavidin donor beads in Lysis/Detection buffer (0.1% BSA, 0.3% Tween-20 and 5 mM HEPES, pH7.4) for 45 min at the room temperature. Fluorescence changes were read using a Fusion-alpha HT microplate reader.cAMP Assay: A 384-well drug plate was prepared to contain test compounds, PGE2 and cAMP in 16 serial dilutions in triplicate, using a Biomek station. HEK-EBNA cells expressing a target PG receptor subtype (EP2 or EP4) were suspended in a stimulation buffer (HBSS, 0.1% BSA, 0.5 mM IBMX and 5 mM HEPES, pH 7.4) in a density of 104 cells/5 μl. The reaction was initiated by mixing 5 μL drug dilutions with 5 μl of HEK-EBNA cells in a well, carried out for 30 min at room temperature, and followed by the addition of 5 μl anti-cAMP acceptor beads in the control buffer with Tween-20 (25 mM NaCl, 0.03% Tween-20, 5 mM HEPES, pH7.4). After 30 min in the dark at room temperature, the mixtures were incubated with 15 μl biotinylated-cAMP/strpavidin donor beads in Lysis/Detection buffer (0.1% BSA, 0.3% Tween-20 and 5 mM HEPES, pH7.4) for 45 min at the room temperature. Fluorescence changes were read using a Fusion-alpha HT microplate reader.

Agonist activity at human EP4 receptorAgonist activity at human EP4 receptor

Agonist activity at human EP4 receptorAgonist activity at human EP4 receptor

Effective concentration which increases intracellular c-AMP production in mouse Prostanoid EP4 receptorEffective concentration which increases intracellular c-AMP production in mouse Prostanoid EP4 receptor

Partial agonist activity at human EP4 receptor expressed in HEK293-AEQ17 cells assessed as cAMP accumulation by aequorin luminescence assayPartial agonist activity at human EP4 receptor expressed in HEK293-AEQ17 cells assessed as cAMP accumulation by aequorin luminescence assay

Agonist activity at rat EP4 receptorAgonist activity at rat EP4 receptor

Agonist activity at rat EP4 receptor expressed in CHO cells assessed as cAMP production after 10 mins by radioimmunoassayAgonist activity at rat EP4 receptor expressed in CHO cells assessed as cAMP production after 10 mins by radioimmunoassay

cAMP Assay: A 384-well drug plate was prepared to contain test compounds, PGE2 and cAMP in 16 serial dilutions in triplicate, using a Biomek station. HEK-EBNA cells expressing a target PG receptor subtype (EP2 or EP4) were suspended in a stimulation buffer (HBSS, 0.1% BSA, 0.5 mM IBMX and 5 mM HEPES, pH 7.4) in a density of 104 cells/5 μl. The reaction was initiated by mixing 5 μL drug dilutions with 5 μl of HEK-EBNA cells in a well, carried out for 30 min at room temperature, and followed by the addition of 5 μl anti-cAMP acceptor beads in the control buffer with Tween-20 (25 mM NaCl, 0.03% Tween-20, 5 mM HEPES, pH7.4). After 30 min in the dark at room temperature, the mixtures were incubated with 15 μl biotinylated-cAMP/strpavidin donor beads in Lysis/Detection buffer (0.1% BSA, 0.3% Tween-20 and 5 mM HEPES, pH7.4) for 45 min at the room temperature. Fluorescence changes were read using a Fusion-alpha HT microplate reader.cAMP Assay: A 384-well drug plate was prepared to contain test compounds, PGE2 and cAMP in 16 serial dilutions in triplicate, using a Biomek station. HEK-EBNA cells expressing a target PG receptor subtype (EP2 or EP4) were suspended in a stimulation buffer (HBSS, 0.1% BSA, 0.5 mM IBMX and 5 mM HEPES, pH 7.4) in a density of 104 cells/5 μl. The reaction was initiated by mixing 5 μL drug dilutions with 5 μl of HEK-EBNA cells in a well, carried out for 30 min at room temperature, and followed by the addition of 5 μl anti-cAMP acceptor beads in the control buffer with Tween-20 (25 mM NaCl, 0.03% Tween-20, 5 mM HEPES, pH7.4). After 30 min in the dark at room temperature, the mixtures were incubated with 15 μl biotinylated-cAMP/strpavidin donor beads in Lysis/Detection buffer (0.1% BSA, 0.3% Tween-20 and 5 mM HEPES, pH7.4) for 45 min at the room temperature. Fluorescence changes were read using a Fusion-alpha HT microplate reader.

cAMP Assay: 1. Seed cells on an EP2 or EP4 STEP plate at a density of 40,000-80,000 cells/well in 200 uL of reduced serum medium containing 0.5% FBS. Place the plate in a 37° C. incubator with 5% CO2 and incubate overnight. 2. After 16-18 hours of incubation, aspirate the culture media from each well. 3. Add 200 ul of culture medium containing 500 uM IBMX (an inhibitor of cAMP phosphodiesterase) and different concentration of test compounds to the assigned wells. For each test compound, at least 8 concentrations starting at highest 10 M and lowest 0.01 pM were tested. In addition each concentration had triplicates. A PGE2 curve (concentrations from lowest to highest, 0 pM, 0.384 pM, 1.92 pM, 9.6 pM, 48 pM, 240 pM, 1200 pM, and 6000 pM) was always run in parallel with test compounds. 4. Incubate the cells in a cell culture incubator for 30 minutes. 5. Centrifuge the plate at 1,000x rpm for 10 minutes. 6. Aspirate the supernatant.cAMP Assay: 1. Seed cells on an EP2 or EP4 STEP plate at a density of 40,000-80,000 cells/well in 200 uL of reduced serum medium containing 0.5% FBS. Place the plate in a 37° C. incubator with 5% CO2 and incubate overnight. 2. After 16-18 hours of incubation, aspirate the culture media from each well. 3. Add 200 ul of culture medium containing 500 uM IBMX (an inhibitor of cAMP phosphodiesterase) and different concentration of test compounds to the assigned wells. For each test compound, at least 8 concentrations starting at highest 10 M and lowest 0.01 pM were tested. In addition each concentration had triplicates. A PGE2 curve (concentrations from lowest to highest, 0 pM, 0.384 pM, 1.92 pM, 9.6 pM, 48 pM, 240 pM, 1200 pM, and 6000 pM) was always run in parallel with test compounds. 4. Incubate the cells in a cell culture incubator for 30 minutes. 5. Centrifuge the plate at 1,000x rpm for 10 minutes. 6. Aspirate the supernatant.

Agonist activity at rat EP4 receptorAgonist activity at rat EP4 receptor

Activity at rat EP4 transfected in HEK293 cells by cAMP accumulationActivity at rat EP4 transfected in HEK293 cells by cAMP accumulation

Agonist activity at rat EP4 receptor expressed in CHO cells assessed as cAMP production after 10 mins by radioimmunoassayAgonist activity at rat EP4 receptor expressed in CHO cells assessed as cAMP production after 10 mins by radioimmunoassay

Agonist activity at human EP4 receptorAgonist activity at human EP4 receptor

Agonist activity against recombinant prostanoid EP4 receptor stably transfected in CHO cellsAgonist activity against recombinant prostanoid EP4 receptor stably transfected in CHO cells

Agonist activity at rat EP4 receptor expressed in CHO cells assessed as cAMP production after 10 mins by radioimmunoassayAgonist activity at rat EP4 receptor expressed in CHO cells assessed as cAMP production after 10 mins by radioimmunoassay

Agonist activity at rat EP4 receptor expressed in CHO cells assessed as cAMP production after 10 mins by radioimmunoassayAgonist activity at rat EP4 receptor expressed in CHO cells assessed as cAMP production after 10 mins by radioimmunoassay

Agonist activity at rat EP4 receptor expressed in CHO cells assessed as cAMP production after 10 mins by radioimmunoassayAgonist activity at rat EP4 receptor expressed in CHO cells assessed as cAMP production after 10 mins by radioimmunoassay

Agonist activity at rat EP4 receptor expressed in CHO cells assessed as cAMP production after 10 mins by radioimmunoassayAgonist activity at rat EP4 receptor expressed in CHO cells assessed as cAMP production after 10 mins by radioimmunoassay

Agonist activity at recombinant human EP4 receptor expressed in CHO cells assessed as increase in intracellular cAMP level by EIAAgonist activity at recombinant human EP4 receptor expressed in CHO cells assessed as increase in intracellular cAMP level by EIA

Activity at rat EP4 transfected in HEK293 cells by cAMP accumulationActivity at rat EP4 transfected in HEK293 cells by cAMP accumulation

Agonist activity at rat EP4 receptor expressed in CHO cells assessed as cAMP production after 10 mins by radioimmunoassayAgonist activity at rat EP4 receptor expressed in CHO cells assessed as cAMP production after 10 mins by radioimmunoassay

Activity at rat EP4 transfected in HEK293 cells by cAMP accumulationActivity at rat EP4 transfected in HEK293 cells by cAMP accumulation

Agonist activity at rat EP4 receptor expressed in CHO cells assessed as cAMP production after 10 mins by radioimmunoassayAgonist activity at rat EP4 receptor expressed in CHO cells assessed as cAMP production after 10 mins by radioimmunoassay

Radioligand Binding Assay: Assay Volume and Format:200 μl in 96-well plateCell membrane homogenates (20 μg protein) are incubated for 120 min at 22° C. with 0.5 nM [3H]PGE2 in the absence or presence of the test compound in a buffer containing 10 mM MES/KOH (pH 6.0), 10 mM MgCl2 and 1 mM EDTA.Nonspecific binding is determined in the presence of 10 M PGE2.Following incubation, the samples are filtered rapidly under vacuum through glass fiber filters (GF/B, Packard) presoaked with 0.3% PEI and rinsed several times with ice-cold 50 mM Tris-HCl using a 96-sample cell harvester (Unifilter, Packard). The filters are dried then counted for radioactivity in a scintillation counter (Topcount, Packard) using a scintillation cocktail (Microscint 0, Packard).Radioligand Binding Assay: Assay Volume and Format:200 μl in 96-well plateCell membrane homogenates (20 μg protein) are incubated for 120 min at 22° C. with 0.5 nM [3H]PGE2 in the absence or presence of the test compound in a buffer containing 10 mM MES/KOH (pH 6.0), 10 mM MgCl2 and 1 mM EDTA.Nonspecific binding is determined in the presence of 10 M PGE2.Following incubation, the samples are filtered rapidly under vacuum through glass fiber filters (GF/B, Packard) presoaked with 0.3% PEI and rinsed several times with ice-cold 50 mM Tris-HCl using a 96-sample cell harvester (Unifilter, Packard). The filters are dried then counted for radioactivity in a scintillation counter (Topcount, Packard) using a scintillation cocktail (Microscint 0, Packard).

Antagonist activity at human EP4 receptor expressed in HEK293 cells assessed as inhibition of PGE2-stimulated cAMP production after 1 hr by HTRF assayAntagonist activity at human EP4 receptor expressed in HEK293 cells assessed as inhibition of PGE2-stimulated cAMP production after 1 hr by HTRF assay