title: The definition of an MB related specificity by a monoclonal antibody.
abstract: A number of monoclonal antibodies have been described that react with monomorphic and polymorphic Ia-like specificities on human B cells, but it is not clear whether these react with HLA-DR encoded molecules or with the products of other closely linked genes within the MHC, such as MB, MT, or DC 1 antigens. A monoclonal antibody is described herein (MC-26.1) which detects a new Ia-like specificity as shown by B-cell reactivity, chemistry, family studies, including recombinant family and coprecipitation studies. The latter studies showed that specificity detected by the MC-26.1 antibody coprecipitated with determinants detected by conventional anti-MB3 and MT3, but not with HLA-DR4 antisera. The determinant was polymorphic but not related to any of the known MB or MT specificities. However, cross-reactions were demonstrated by the variability of reaction on different individuals. Coprecipitation studies indicate that the antigen defined by MC-26.1 coprecipitates with MB and MT specificities suggesting that the antibody defines a new specificity on the MB3 and MT3 molecules.
mesh_terms: D000818:Animals; D000911:Antibodies, Monoclonal / Q000276:immunology*; D001402:B-Lymphocytes / Q000276:immunology; D002460:Cell Line; D000939:Epitopes / Q000276:immunology; D005260:Female; D005802:Genes, MHC Class II; D006680:HLA Antigens / Q000235:genetics; D015234:HLA-A Antigens; D015235:HLA-B Antigens; D006684:HLA-DR Antigens; D000949:Histocompatibility Antigens Class II / Q000276:immunology*; D006801:Humans; D007945:Leukemia, Lymphoid / Q000276:immunology; D008297:Male; D051379:Mice
chemical_list: D000911:Antibodies, Monoclonal; D000939:Epitopes; D006680:HLA Antigens; D015234:HLA-A Antigens; D015235:HLA-B Antigens; D006684:HLA-DR Antigens; D000949:Histocompatibility Antigens Class II