Inhibition of the growth and differentiation of erythroid precursor cells by an endotoxin-induced mediator from peritoneal macrophages.
Conditioned medium from cultures of mouse macrophages incubated with endotoxin in a serum-free medium contains an inhibitor of the growth and differentiation of erythroid precursor cells of mouse Friend virus-transformed erythroleukemia cells. Endotoxin itself has no inhibitory effect. The endotoxin-induced macrophage mediator inhibits the growth and differentiation of dimethyl sulfoxide-, hexamethylenebisacetamide-, butyric acid-, and hypoxanthine-induced cells but has no effect on hemin-induced cells. The conditioned medium has its maximal inhibitory effect on committed erythroid precursor cells, a decreased effect on uncommitted stem cells, and no effect on fully differentiated erythroid cells. These results demonstrate that endotoxin stimulation of macrophages leads to the production of a humoral factor(s) which is critical for the growth and differentiation of erythroid precursor cells.
D000818:Animals; D001202:Ascitic Fluid / Q000166:cytology; D002454:Cell Differentiation / Q000187:drug effects; D002455:Cell Division / Q000187:drug effects; D002478:Cells, Cultured; D004305:Dose-Response Relationship, Drug; D004731:Endotoxins / Q000494:pharmacology*; D004920:Erythropoiesis / Q000187:drug effects*; D008264:Macrophages / Q000502:physiology*; D051379:Mice
D004731:Endotoxins