Monoclonal helper T cells induce B cell responses to T-independent antigens: antigen-specific T cells are directly stimulated by activated B cells in the absence of antigen.
Efficient B cell responses to most polysaccharide antigens such as TNP-PAA or TNP-Ficoll require factors produced by activated T cells. However, the mechanism of T cell activation during such responses has not been established, because these antigens do not activate T cells, either directly or in conjunction with I-A gene products. We used a panel of antigen-specific monoclonal helper T cells to study T cell activation during the course of such responses. We show that activated I-A-identical B cells directly stimulate these monoclonal T cells, and that this stimulation is in the absence of nominal antigen. The high frequency of inducer cells that are stimulated by activated B cells suggests a major biologic role for this novel pathway of T cell activation.
DeKruyff
R H
RH
Clayberger
C
C
Cantor
H
H
D000818:Animals; D000911:Antibodies, Monoclonal; D000917:Antibody Formation; D000941:Antigens / Q000276:immunology*; D001402:B-Lymphocytes / Q000276:immunology*; D002478:Cells, Cultured; D002999:Clone Cells; D007126:Immunoglobulin Allotypes; D008213:Lymphocyte Activation; D051379:Mice; D008815:Mice, Inbred Strains; D013045:Species Specificity; D013601:T-Lymphocytes / Q000276:immunology; D006377:T-Lymphocytes, Helper-Inducer / Q000276:immunology*
D000911:Antibodies, Monoclonal; D000941:Antigens; D007126:Immunoglobulin Allotypes