FIGURE 5.

Inhibition of cAMP and calcium mobilization triggered by CCR5. A, measurement of BRET signal in HEK293T cells coexpressing the cAMP biosensor and CCR5 and stimulated sequentially by chemokines and forskolin. The results were normalized for the basal signal in absence of stimulation (0%), and the maximal response was obtained with forskolin only (100%). The data represent the means ± S.E. of three independent experiments. B, calcium mobilization was measured in CHO-K1 cells using the aequorin-based functional assay. Cells expressing CCR5 were stimulated with increasing concentrations of chemokines, and luminescence was recorded for 30 s. The results were normalized for the basal luminescence in absence of agonist (0%), and the maximal response was obtained with 25 μm ATP (100%). The data represent the means ± S.E. of three independent experiments.