title: The influence of interferon-gamma and various phagocytic stimuli on the expression of MHC-class II antigens on human monocytes--relation to the generation of reactive oxygen intermediates.
abstract: Human monocytes show a dose-dependent decrease of the MHC-class II antigen expression (HLA-DR and HLA-DQ) after addition of zymosan or Staphylococcus aureus Cowan I particles. Interferon-gamma did not prevent this process. The expression of MHC-class I antigens was not affected. The dose-response and kinetic curves showed individual differences. An association between the capacity to form reactive oxygen intermediates and the downregulation of MHC-class II antigen expression was observed. In addition, after digestion of the phagocytosed particles interferon-gamma could restore the MHC-class II antigen expression on the cultured monocytes. The possible biological significance of these interactions between interferon-gamma and phagocytosis for the function of monocytes/macrophages in the local inflammatory process is discussed.
mesh_terms: D000911:Antibodies, Monoclonal; D005455:Fluorescent Antibody Technique; D006649:Histocompatibility Antigens / Q000032:analysis; D006706:Homeostasis; D006801:Humans; D007371:Interferon-gamma / Q000494:pharmacology*; D007700:Kinetics; D008163:Luminescent Measurements; D008285:Major Histocompatibility Complex; D009000:Monocytes / Q000187:drug effects / Q000276:immunology*; D010100:Oxygen / Q000097:blood*; D010587:Phagocytosis; D011994:Recombinant Proteins / Q000494:pharmacology*
chemical_list: D000911:Antibodies, Monoclonal; D006649:Histocompatibility Antigens; D011994:Recombinant Proteins; D007371:Interferon-gamma; D010100:Oxygen