The role of G protein coupling in the regulation of GCP-2–induced CXCR2 internalization.

CXCR2-expressing HEK 293 cells were incubated with 360 ng/mL or 1000 ng/mL GCP-2 for 2 hours at 37°C. Prior to (for 2 hours) and during the exposure to GCP-2, the cells were treated with 100 ng/mL pertussis toxin (PTx) at 37°C. The cells were washed and stained with anti-CXCR2–specific antibodies, and subjected to fluorescence activated cell sorting (FACS) analysis as described in “Materials and methods.” Each value represents the mean ± SD of over 4 independent experiments. * P < .002 for internalization induced by 1000 ng/mL GCP-2 in the absence of, vs in the presence of, pertussis toxin (PTx).