Adult hemoglobins are synthesized in murine fetal hepatic erythropoietic cells

The hemoglobins present in murine fetal hepatic erythroblasts on days 12–15 of gestation were studied by biochemical and immunocytologic techniques. In addition, fetal hepatic hemopoietic progenitor cells obtained from normal and mutant f/f mouse fetuses on days 11–13 of gestation were cultured in vitro with added erythropoietin and adult spleen cell conditioned medium to form large erythroid colonies. In all instances, adult hemoglobin synthesis was detected in the fetal hepatic erythroblasts and in the erythroid cell cultures in vitro. The tumor promoter, 12-O-tetradecanoylphorbol 13-acetate, enhanced the fetal hepatic erythroid colony growth in vitro, but did not alter the hemoglobin phenotypic expression.