GPR65 regulates eosinophil cAMP production and viability. Eosinophils were isolated from the spleens of GPR65^+/+ or GPR65^−/− mice; eosinophils were incubated in media of various acidity (A) or forskolin at pH 7.0 (B) for 30 minutes in the presence of IBMX, and accumulated intracellular cAMP was measured via an ELISA from eosinophil lysates. n = 3 mice per group. Results shown as the mean intracellular cAMP ± SD. Representative experiments (of 3) are shown. Viability analysis of GPR65^+/+ and GPR65^−/− eosinophils after a 5-hour ex vivo incubation at pH 7.5 and 6.0 (C). Results are representative of 3 time-course and 8 5-hour incubation experiments. Results are shown as the mean ± SD of triplicate incubations.