Regulated Production of a Pleiotropic Cytokine-Platelet-Derived Growth Factor-ByDifferentiating Erythroid Cells in Vitro and in Vivo

摘要

Erythroid progenitor growth in vitro is stimulated by exogenous platelet-derivedgrowth factor (PDGF). We now report that both normal and transformed erythroid progenitor cells produce authentic PDGF in vitro and in vivo. Importantly, this production is highly regulated during erythropoiesis. Addition of soluble lysates from Rauscher murine erythroleukemia cells-an erythropoietin-responsive model progenitor cell line-to quiescent BALB/c 3T3 fibroblasts resulted in a mitogenic response identical to that observed with the addition of authentic recombinant PDGF. Polyclonal and monoclonal anti-PDGF antibodies immunoabsorbed 50-100% of this activity. Induction of Rauscher cell differentiation in vitro with dimethyl sulfoxide or erythropoietin for 48-72 hr markedly upregulated PDGF production by