Effects of SDF-1 on the expression of CD62 by megakaryocytes. (A,B,C) Examples of double-color staining with anti-CD62 in combination with anti-CD41a (A) or with control antibodies (B) and (C). Primary cultured cells were either left unstimulated (thick line) or stimulated for 10 minutes with either thrombin (1 U/mL, thin line) or SDF-1 (300 ng/mL, broken line). CD62 staining in combination with CD41a staining was then compared by FACS analysis as described in Materials and Methods. The analysis was performed in CD41a^low (D) and CD41a^high (E) gates as defined in (A) and in platelets (F). These data are representative of four experiments.