Effects of platelet derived growth factor, epidermal growth factor and transforming growth factor-beta on the growth of human marrow fibroblasts.

The effects of three growth factors contained in platelets on human bone marrow fibroblasts as well as fibroblast colony-forming cells were investigated to clarify the pathogenesis of marrow fibrosis frequently associated with myeloproliferative disorders. Two growth factors, platelet derived growth factor (PDGF) and epidermal growth factor (EGF), cooperatively stimulated the growth of passaged fibroblasts as well as fibroblast colony-forming cells. Transforming growth factor-beta augmented the growth of fibroblasts at low concentrations in the presence of EGF and/or PDGF, but inhibited that of colony-forming cells in the presence of PDGF or EGF. These results suggest that the growth of fibroblasts causing marrow fibrosis might be finely regulated, depending on the concentrations of growth factors released or leaked from platelets or megakaryocytes into marrow environment.