Modulation of human B-lymphocyte receptors for IgG does not affect HLA-DR antigens.
Receptors for the Fc portion of immunoglobulin G (Fc gamma R) on the surface of human peripheral T cells can be modulated on contact with antigen-antibody immune complexes (IgG-IC). Our results demonstrate that the Fc gamma R present on the surface of human B cells are also modulated on exposure to IgG-IC. Furthermore, the expression of HLA-DR molecules is not affected by the IgG-IC induced disappearance of Fc gamma R. In fact, the percentage of HLA-DR-positive cells and the relative amount of HLA-DR molecules on individual B cells analysed by flow microfluorometry was shown not to be influenced by Fc gamma R modulation. Moreover, pretreatment of cells with monoclonal antibodies directed against non-polymorphic determinants of HLA-DR antigens did not prevent the binding of IgG-coated ox erythrocytes. These results argue against a structural relationship between Fc gamma R and HLA-DR molecules on the surface of the B-cell populations investigated here.
D000911:Antibodies, Monoclonal / Q000276:immunology; D000936:Antigen-Antibody Complex / Q000378:metabolism; D001402:B-Lymphocytes / Q000276:immunology* / Q000378:metabolism; D002469:Cell Separation; D005434:Flow Cytometry; D000949:Histocompatibility Antigens Class II; D006801:Humans; D011947:Receptors, Antigen, B-Cell; D011961:Receptors, Fc; D017452:Receptors, IgG; D011971:Receptors, Immunologic; D012397:Rosette Formation
D000911:Antibodies, Monoclonal; D000936:Antigen-Antibody Complex; D000949:Histocompatibility Antigens Class II; D011947:Receptors, Antigen, B-Cell; D011961:Receptors, Fc; D017452:Receptors, IgG; D011971:Receptors, Immunologic