title: Activation of immunoglobulin allotype-specific T cells by B cells.
abstract: To investigate the role of Ia and immunoglobulin (Ig) molecules of B cells in alloantigen-specific and nominal antigen-specific T-cell activations, the ability of B cells to stimulate Ig allotype-specific T cells was examined. T15-primed B10.BR T cells responded to MOPC 315 (IgA myeloma protein derived from BALB/c) as well as T15 but not to MOPC31c (IgG1 myeloma protein). These T cells were stimulated by papain-digested Fc fragment of T15. Thus, T15-primed B10.BR T cells were shown to be specific for Ig allotype of T15, that is, Igh-2a. T15-specific B10.BR T cells were selected by 10-day cultures with T15 in vitro. They responded to BALB.K spleen cells without addition of soluble T15 antigen to the assay culture. Stimulator cells in this mixed lymphocyte reaction (MLR)-like response between T15-specific B10.BR T cells and BALB.K spleen cells were Thy-1-, Ia+ cells and these responses were blocked by anti-Iak antibodies. Furthermore, Sephadex G-10-passed BALB.K B cells stimulated the proliferation of T15-specific B10.BR T cells, while they failed to stimulate allogeneic BALB/c spleen cells. The stimulating ability of B cells in this MLR-like response of T15-specific B10.BR T cells was shown to be genetically restricted, namely, both H-2 and non-H-2 genes are involved in the manifestation of the stimulating ability. This system will provide a useful model for studying the role of B-cell surface Ig and Ia molecules in the activation of antigen-specific T cells and alloreactive T cells.
mesh_terms: D000818:Animals; D000918:Antibody Specificity; D001402:B-Lymphocytes / Q000276:immunology*; D002460:Cell Line; D002469:Cell Separation; D002850:Chromatography, Gel; D005260:Female; D005802:Genes, MHC Class II; D006183:H-2 Antigens / Q000235:genetics; D000949:Histocompatibility Antigens Class II / Q000276:immunology; D007126:Immunoglobulin Allotypes / Q000276:immunology*; D008213:Lymphocyte Activation; D007959:Lymphocyte Culture Test, Mixed; D008297:Male; D051379:Mice; D008805:Mice, Inbred A; D008807:Mice, Inbred BALB C; D009194:Myeloma Proteins / Q000276:immunology; D013601:T-Lymphocytes / Q000276:immunology*
chemical_list: D006183:H-2 Antigens; D000949:Histocompatibility Antigens Class II; D007126:Immunoglobulin Allotypes; D009194:Myeloma Proteins