title: Serum-mediated inhibition of the interferon-gamma-induced HLA-DR expression on monocytes in patients with psoriasis.
abstract: Psoriatic patients have a decreased proportion of monocytes expressing class II major histocompatibility complex antigens (DR+ monocytes) in their peripheral blood. The expression of the DR antigen on monocytes after culture in the presence of either autologous lymphocytes (endogenous interferon-gamma, IFN-gamma) or exogenous IFN-gamma was investigated. In normal AB serum the lymphocytes of the majority of the patients showed a spontaneous IFN-gamma production which was sufficient for DR antigen induction, while the monocytes displayed approximate normal susceptibility to exogenous IFN-gamma as judged by DR antigen expression. However, the sera of psoriatic patients contained one or more factors that interfered with the IFN-gamma-mediated DR antigen expression on cultured monocytes of the same patients. Restoration of IFN-gamma-induced DR antigen expression on monocytes in the presence of the patient's sera was achieved by the addition of superoxide dismutase, 2-mercaptoethanol, or indomethacin. The clinical significance of these observations is discussed.
mesh_terms: D000954:Antigens, Surface / Q000032:analysis; D002478:Cells, Cultured; D006681:HLA-D Antigens / Q000276:immunology*; D006684:HLA-DR Antigens / Q000276:immunology*; D006801:Humans; D007213:Indomethacin / Q000494:pharmacology; D007371:Interferon-gamma / Q000037:antagonists & inhibitors / Q000494:pharmacology*; D008214:Lymphocytes / Q000276:immunology; D008623:Mercaptoethanol / Q000494:pharmacology; D009000:Monocytes / Q000276:immunology*; D011565:Psoriasis / Q000097:blood / Q000276:immunology*; D013482:Superoxide Dismutase
chemical_list: D000954:Antigens, Surface; D006681:HLA-D Antigens; D006684:HLA-DR Antigens; D008623:Mercaptoethanol; D007371:Interferon-gamma; D013482:Superoxide Dismutase; D007213:Indomethacin