title: Two distinct azobenzenearsonate-specific helper T-cell subpopulations mediate different forms of T-B cooperation.
abstract: Popliteal lymph node T cells from mice footpad-primed with azobenzenearsonate (ABA)-protein conjugates were able to help the anti-trinitrophenyl (TNP) and anti-ABA plaque-forming cell (PFC) responses of normal syngeneic spleen cells cultured in vitro with TNP-ABA-keyhole limpet haemocyanin. Enrichment in ABA-specific helper cells was obtained by positive selection of ABA-primed T cells on ABA-pulsed syngeneic macrophages. The ABA-specific T cells induced by ABA-protein priming are able to help the anti-TNP PFC response of normal B cells through recognition of the ABA determinant either unlinked to TNP (ABA and TNP separately presented to T and B cells) or linked to TNP (ABA and TNP presented as moieties of the same molecule). These two mechanisms of T-B cooperation are mediated by two different ABA-specific helper T-cell subpopulations, which can be distinguished by their different radiosensitivities: the former mechanism is mediated by radioresistant T cells, whereas the latter is mediated by radiosensitive T cells. Both helper T-cell subpopulations bind the ABA-pulsed syngeneic macrophages, demonstrating the presence of ABA-specific receptors on both cell types.
mesh_terms: D000818:Animals; D001391:Azo Compounds / Q000276:immunology*; D001402:B-Lymphocytes / Q000276:immunology; D000939:Epitopes; D005260:Female; D006433:Hemocyanins / Q000276:immunology; D006462:Hemolytic Plaque Technique; D008211:Lymphocyte Cooperation; D008264:Macrophages / Q000276:immunology; D051379:Mice; D008810:Mice, Inbred C57BL; D008811:Mice, Inbred DBA; D011948:Receptors, Antigen, T-Cell; D013601:T-Lymphocytes / Q000276:immunology; D006377:T-Lymphocytes, Helper-Inducer / Q000145:classification / Q000276:immunology* / Q000528:radiation effects; D014301:Trinitrobenzenes / Q000276:immunology; D010132:p-Azobenzenearsonate / Q000276:immunology*
chemical_list: D001391:Azo Compounds; D000939:Epitopes; D011948:Receptors, Antigen, T-Cell; D014301:Trinitrobenzenes; D010132:p-Azobenzenearsonate; D006433:Hemocyanins