C3a and C5a stimulate migration of HMC-1 cells via a pertussis toxin-sensitive G protein. After treatment of HMC-1 cells with pertussitoxin at 2 μg/mL for 90 minutes, cells were stimulated with C3a (1 μg/mL, 100 nmol/L) and C5a (0.1 μg/mL, 10 nmol/L) in Boyden chambers. Results are expressed as mean ± SEM of 3 to 13 experiments (n = 3 to 13).