Fig. 4. CXCL12 stimulation induces actin polymerization, associated with local CXCR4 accumulation, in TAM2D2 cells but not in C2B transfectants. Beads coated with fibronectin and CXCL12 (arrows) were allowed to adhere to cells on coverslips, fixed after 10 minutes and stained with (A) phalloidin (for actin) or (B) CXCR4 antibody. At least 30 cells per condition were analyzed using confocal microscopy. Beads coated with fibronectin but not CXCL12 were used as a negative control and did not have an effect on TAM2D2 cells (Fig. 4C). Experiments were repeated three times.