Induction of colonies of hemoglobin-synthesizing cells by erythropoietin in vitro.

A culture method has been developed in which erythroid colonies are produced in vitro from hemopoietic cells from the livers of 13-day fetuses of C3H(f)/Bi mice. Heme synthesis by the cultures was correlated with the presence of these colonies, and the hemoglobin produced was shown to be electrophoretically normal. The individual colonies were identified as erythroid since they were erythropoietin-dependent, positively stained by the histochemical "Lepehne" procedure for hemoglobin, and labeled by (59)Fe radioautography. Evidence is presented that the development of these colonies is under separate control from that of granulocytic colonies found in the same cultures.