title: Role of antigen-specific B cells in the induction of SRBC-specific T cell proliferation.
abstract: In this study, we ask whether antigen presentation can be effected by antigen-activated B cells. Antigen-dependent in vitro proliferation of T cells from mice primed with SRBC or HoRBC occurs in the presence of B cells primed to the relevant antigen. B cells prepared from lymph nodes of mice primed with irrelevant antigens are not effective antigen-presenting cells for RBC-specific T cell proliferation over a wide range of SRBC doses. This is true even when both RBC and the antigen to which the B cells are primed are included in the culture. In contrast, B cells specific for a hapten determinant coupled to SRBC are able to support proliferation of T cells specific for SRBC determinants. We conclude from these data that antigen-specific B cells play a role in the induction of T cell proliferative responses to SRBC and HoRBC antigens. Two models are proposed: either B cells, upon antigen interaction with surface antibody, are able to act as accessory cells to induce Ia-dependent proliferation of immune T cells; or B cells augment the T cell proliferative response by secretion of antibody, leading to opsonization of the antigen for macrophage uptake and presentation.
mesh_terms: D000818:Animals; D000921:Antibody-Producing Cells / Q000276:immunology; D001402:B-Lymphocytes / Q000276:immunology*; D000939:Epitopes; D006241:Haptens / Q000276:immunology; D006736:Horses; D007519:Isoantigens / Q000008:administration & dosage / Q000276:immunology*; D008213:Lymphocyte Activation; D008211:Lymphocyte Cooperation; D051379:Mice; D008808:Mice, Inbred CBA; D010047:Ovalbumin / Q000276:immunology; D011947:Receptors, Antigen, B-Cell / Q000276:immunology / Q000502:physiology; D012756:Sheep; D013601:T-Lymphocytes / Q000276:immunology*
chemical_list: D000939:Epitopes; D006241:Haptens; D007519:Isoantigens; D011947:Receptors, Antigen, B-Cell; D010047:Ovalbumin