Specificity of hemin action in vivo at early stages of hematopoietic cell differentiation.

The effects of a single injection of hemin on murine marrow BFU-E and CFU-S were assessed to determine whether hemin is as effective in augmenting primitive (day 7) BFU-E levels in situ as it is in vitro and to assess hemin's action on transplantable pluripotent stem cells (CFU-S). The results show that hemin exerts a cell-specific enhancement of both BFU-E marrow levels and cell cycling within 6 h of its administration in vivo. No such effect on CFU-S was observed.