SCF potentiates the ability of Epo to support wild-type fetal liver CFU-e colony formation. Fetal liver cells were cultured in methylcellulose containing Epo (2 U/mL) and/or rSCF (100 ng/mL). The methylcellulose medium was either serum free, or contained 10% PDS. Results are the mean ± SD of triplicate samples.