title: Down regulation of human monocyte differentiation antigens by interferon gamma.
abstract: The role of IFN-gamma in the activation and differentiation of human peripheral blood monocytes was investigated. Recombinant IFN-gamma induced a decrease in the expression of monocyte differentiation antigens (Mo2 and 63D3) and, to a lesser extent, the C3bi receptor. Conversely, class II histocompatibility antigen expression increased on monocytes exposed to IFN-gamma. The antigen modulating effect of IFN-gamma was maximal on freshly isolated monocytes, with diminished potency if added to monocytes that had been cultivated in vitro for 1 to 3 days. Experiments to determine the fate of the down-regulated antigens on interferon-treated cells failed to demonstrate intracellular antigen due to internalization. We suggest that Mo2 and 63D3 may be considered "inverse" activation antigens; i.e., their expression is decreased in monocytes activated by interferon.
mesh_terms: D000911:Antibodies, Monoclonal; D000954:Antigens, Surface / Q000276:immunology*; D002454:Cell Differentiation / Q000187:drug effects; D002478:Cells, Cultured; D004305:Dose-Response Relationship, Drug; D004334:Drug Administration Schedule; D006801:Humans; D007213:Indomethacin / Q000494:pharmacology; D007370:Interferon Type I / Q000494:pharmacology; D007371:Interferon-gamma / Q000008:administration & dosage / Q000494:pharmacology*; D007375:Interleukin-1 / Q000494:pharmacology; D009000:Monocytes / Q000166:cytology / Q000276:immunology*; D013997:Time Factors
chemical_list: D000911:Antibodies, Monoclonal; D000954:Antigens, Surface; D007370:Interferon Type I; D007375:Interleukin-1; D007371:Interferon-gamma; D007213:Indomethacin