Role of hemopoietic growth factors in regeneration of hemopoiesis during etoposide-induced myelosuppression.

We studied structural and functional organization of the bone marrow, production of hemopoietic growth factors by hemopoietic cells, and plasma colony-stimulating and erythropoietic activities in CBA/CaLac mice treated with etoposide. The effects of etoposide on cultured hemopoietic and microenvironmental cells were also evaluated. Our results indicate that hemopoietic growth factors secreted by adherent bone marrow cells play the major role in the normalization of hemopoiesis during etoposide-induced myelosuppression.