The selective enhancing influence of hemin and products of human erythrocytes on colony formation by human multipotential (CFUGEMM) and erythroid (BFUE) progenitor cells in vitro.

The influence of erythrocytes, extracts of erythrocytes and hemin was assessed on colony formation in vitro by human bone marrow multipotential (CFUGEMM), erythroid (BFUE) and granulocyte-macrophage (CFUGM) progenitor cells. Colony formation by CFUGEMM and BFUE present in the low density (less than 1.077 g/cm3) fraction of bone marrow cells was enhanced in the presence of high density (greater than 1.077 g/cm3) bone marrow cells. Erythrocytes, but not leukocytes, present in the high density fraction of cells were responsible for this enhancing effect on colony formation. Extracts of erythrocytes or hemin substituted for the enhancing activity of the intact erythrocytes. This enhancing activity was not apparent on colony formation by bone marrow CFUGM. These results demonstrate a selective enhancing influence on colonies derived from CFUGEMM and BFUE. Erythrocyte products allow the detection of such colonies and may play a role in the growth stimulation of CFUGEMM and BFUE.