title: CDw40 and BLCa-specific monoclonal antibodies detect two distinct molecules which transmit progression signals to human B lymphocytes.
abstract: Two monoclonal antibodies (mAb), MA6 and G28-5, have the common property of detecting markers expressed on both B lymphocytes and carcinomas: BLCa (B lymphocyte carcinoma cross-reacting antigen) and CDw40 (Bp50). A comparison of the reactivity of these mAb revealed that MA6 and G28-5 detect distinct epitopes with different cell line and tissue distributions. L cell transfectants expressing CDw40 were not bound by MA6 anti-BLCa, but were bound by G28-5 anti-CDw40. G28-5 or a CDw40-specific heterantiserum could not block the migration of BLCa, while MA6 antibody could. These results indicate that CDw40 and BLCa are distinct surface molecules. Both G28-5 anti-CDw40 and MA6 anti-BLCa mAb could provide progression signals for B cells activated by appropriate B cell activators such as phorbol esters or anti-immunoglobulin; however, only G28-5 anti-CDw40 and not MA6 was co-stimulatory with the anti-CD20 competence signal, demonstrating a clear difference in the CDw40 and BLCa-mediated progression signals. Apparently, these molecules, although structurally distinct, have related functions in B cell activation.
mesh_terms: D000818:Animals; D000911:Antibodies, Monoclonal / Q000276:immunology*; D000912:Antibodies, Neoplasm / Q000276:immunology; D000944:Antigens, Differentiation, B-Lymphocyte / Q000276:immunology*; D000951:Antigens, Neoplasm / Q000276:immunology; D001402:B-Lymphocytes / Q000276:immunology*; D014408:Biomarkers, Tumor / Q000276:immunology*; D002453:Cell Cycle; D000939:Epitopes / Q000276:immunology; D006801:Humans; D007739:L Cells; D051379:Mice; D011994:Recombinant Proteins / Q000276:immunology; D014407:Tumor Cells, Cultured / Q000276:immunology
chemical_list: D000911:Antibodies, Monoclonal; D000912:Antibodies, Neoplasm; D000944:Antigens, Differentiation, B-Lymphocyte; D000951:Antigens, Neoplasm; D014408:Biomarkers, Tumor; D000939:Epitopes; D011994:Recombinant Proteins