Effect of SCF on the HbF/HbA ratios from cultures of cells from 19 different blood donors.

For each donor, the HbF/HbA ratios were obtained from HPLC analyses of circulating erythrocytes in the peripheral blood (PB) of the donors, erythroid progenitors cultured for 2 weeks in the presence of erythropoietin (EPO; 4 U/mL) alone, and in EPO (4 U/mL) plus SCF (50 ng/mL; E+S). (A) Mean values with SD bars. (B) Values from each donor's matched cultures attached by lines.