Effect of PF4 (0, 76.5, 130, 630, and 1,300 nmol/L) and p34-58 (0, 0.2, 2.2, 22, 76.5, and 130 nmol/L) on the formation of CFU-MK (A), CFU-GM (B), and BFU-E (C) from purified CD34⁺of bone marrow. Values are expressed as the mean ± SEM of triplicate determination obtained from three separate experiments. *P < .01 as compared with control value determined by the Student'st-test. One hundred percent (100%) corresponds to 60 CFU-MK colonies/mL, 70 CFU-GM colonies/mL, and 60 BFU-E/mL, which were grown from control cultures.