Isolation and characterization of an erythroid cell line highly inducible to form erythroid burst-like colonies

The study of induction of Friend erythroleukemic cell lines during the last decade has enriched our understanding of late erythroid differentiation. In comparison, little information is available on early erythroid differentiation. We describe here the isolation and characterization of a highly inducible clone from a murine erythroid cell line, which is capable of forming colonies that possess properties of the early erythroid burst progenitor. We found that a combination of erythropoietin (Epo), spleen conditioned medium (SCM), and plasma from a patient with aplastic anemia (Apa) induces over 95% of cells from this clone (clone 12) to form colonies with the properties of burst or mixed burst blast-like colonies. Examination of the culture conditions of these cells indicated that alpha medium was more efficient for colony induction than Iscove's medium, and that the addition of two-mercaptoethanol did not improve the induction process. These factors (EPo, SCM, and Apa) must be present for 4 days in order for induction to take place. It is hoped that the isolation of this highly inducible cell clone will enrich our understanding of early erythroid differentiation.