Fig. 2. Chemotaxis of peripheral blood mononuclear cells from African-American subjects reading magazines (o) or undergoing a speech task (127). Data are presented as cells migrating to SDF-1 divided random migration of cells to media ± SE. Blood was drawn at BL, immediately after the speech/reading task (0), and 20 minutes after the task (20). The two groups showed a differential change across the session with a significant group x time interaction (F[2,54] = 3.2, p < .05).