Activin A–induced chemotaxis is protein synthesis, PI3Kγ, and G-protein dependent. (A) Effect of B pertussis toxin (PTox; 3 μg/mL) or cycloheximide (CHX; 1 μg/mL) on DC migration in response to activin A, TGF-β, CCL3, and PMA. Results represent average values ( ± SD) of 3 independent experiments. (B) [Ca²⁺]_i in DC stimulated with activin A. One experiment representative of 3 independent determinations is shown. (C) Effect of 10 ng/mL wortmannin on DC migration. (D) Migration to activin A of DCs generated from wild-type (WT) or PI3Kγ^−/− mice. (E) Effect of the viral chemokine-binding protein M3 (100 nM) on DC migration. CCL3, activin A, PMA, and TGF-β were tested at the respective concentrations of 100 ng/mL, 100 ng/mL, 10 nM, and 10 pg/mL. **P < .005 by paired Student t test versus respective control groups.