Induction of erythropoiesis with erythrocyte production in bone marrow cell culture "in vitro".

In the system of long-term bone-marrow culture described by Dexter et al., the differentiation of hematopoietic stem cells into erythropoietic cells is not observed. In this system, bone marrow are grown in a medium supplemented with horse serum. We describe here the induction of erythrocytic maturation in the bone-marrow culture by the addition of 5% fetal calf serum, one or two weeks after seeding the bone-marrow cells. We obtained the persistance up to 5 weeks of erythrocytic production. This phenomenon does not depend on the presence of erythropoietin in fetal calf serum.