title: Insulin-like growth factor I stimulates human erythroid colony formation in vitro.
abstract: The effects of human GH and insulin-like growth factor I on the proliferation and differentiation of erythroid progenitor cells from the bone marrow and peripheral blood of children were studied in a hormone-depleted culture system. Growth of erythroid progenitors was quantified by directly scoring colonies and by biochemical determination of the activity of a cytosolic enzyme of the heme pathway, uroporphyrinogen I synthase. In the presence of erythropoietin, high concentrations (50-100 ng/mL) of human GH induced an increase in the number of erythroid colonies (and their uroporphyrinogen I synthase activity) formed by bone marrow or peripheral blood erythroid precursors. In the same conditions, physiological concentrations of insulin-like growth factor I (0.5-1 ng/mL) stimulated erythroid cell growth and differentiation (P less than 0.03) from bone marrow or peripheral blood.
mesh_terms: D001854:Bone Marrow Cells; D002454:Cell Differentiation / Q000187:drug effects; D002648:Child; D002675:Child, Preschool; D003114:Colony-Forming Units Assay; D004912:Erythrocytes / Q000166:cytology; D004920:Erythropoiesis / Q000187:drug effects*; D013006:Growth Hormone / Q000494:pharmacology; D006801:Humans; D011163:Hydroxymethylbilane Synthase / Q000097:blood; D066298:In Vitro Techniques; D007334:Insulin-Like Growth Factor I / Q000494:pharmacology*; D013002:Somatomedins / Q000494:pharmacology*
chemical_list: D013002:Somatomedins; D007334:Insulin-Like Growth Factor I; D013006:Growth Hormone; D011163:Hydroxymethylbilane Synthase