Differential effects of CD45 CD45R and CD45R0 monoclonal antibodies in modulating human B cell activation.
We have examined the effect of monoclonal antibodies (MoAbs) to different epitopes of the leucocyte common antigen (LCA), CD45, on anti-human immunoglobulin-primed B cell activation. Binding of MoAbs to restricted epitopes present on CD45 glycoproteins of 180 kD and 220 kD (designated CD45R0 and CD45R, respectively) was found to promote B cell proliferation in the presence of T cells. CD45 MoAbs reactive with 'public' determinants on all four constituent members of the LCA family (180, 190, 205, and 220 kD) had either little effect or inhibited the basal B cell response to anti-immunoglobulin priming. Simultaneous immunofluorescent analysis of 5-bromodeoxyuridine incorporation and the expression of CD19 (B cell specific) or CD2 (T cell specific) identified the majority of responder cells as B lymphocytes. CD45R MoAbs significantly enhanced the B cell response to sub-optimal concentrations of interleukin-2. CD45 and CD45R0 MoAbs failed to elicit a similar response. Antibody to the interleukin-2 receptor (anti-Tac) partially blocked the CD45R-driven, T cell-dependent B cell proliferation.
Medical Research Council, Human Genetics Unit, Western General Hospital, Edinburgh, Scotland, UK.
D L
DL
Deane
E
E
Harvey
C M
CM
Steel
D000911:Antibodies, Monoclonal / Q000276:immunology*; D018941:Antigens, CD19; D000943:Antigens, Differentiation / Q000276:immunology*; D000944:Antigens, Differentiation, B-Lymphocyte / Q000276:immunology; D000945:Antigens, Differentiation, T-Lymphocyte / Q000276:immunology; D001402:B-Lymphocytes / Q000276:immunology*; D018801:CD2 Antigens; D000939:Epitopes / Q000276:immunology; D005434:Flow Cytometry; D005455:Fluorescent Antibody Technique; D006649:Histocompatibility Antigens / Q000276:immunology*; D006801:Humans; D007376:Interleukin-2 / Q000494:pharmacology; D017493:Leukocyte Common Antigens; D008213:Lymphocyte Activation / Q000276:immunology*; D011971:Receptors, Immunologic / Q000276:immunology; D013601:T-Lymphocytes / Q000276:immunology
D000911:Antibodies, Monoclonal; D018941:Antigens, CD19; D000943:Antigens, Differentiation; D000944:Antigens, Differentiation, B-Lymphocyte; D000945:Antigens, Differentiation, T-Lymphocyte; D018801:CD2 Antigens; D000939:Epitopes; D006649:Histocompatibility Antigens; D007376:Interleukin-2; D011971:Receptors, Immunologic; D017493:Leukocyte Common Antigens