Antigen-specific T helper clones in a nonresponder strain require augmentation for expression of helper activity. Evidence for a possible antigen presentation defect in B cells.
Hen egg-white lysozyme (HEL)-specific Thy-1+, Lyt-1+2- T cell lines and clones were derived from the nonresponder C57BL/6 strain. Although the antigen-specific proliferative response of these T cells in the presence of syngeneic irradiated spleen cells as a source of antigen-presenting cells (APC) was normal, the same cells were incapable of stimulating B cells to secrete antibody in vitro. This deficiency could, however, be corrected by the addition of an excess of normal T cells or a supernatant from concanavalin A-stimulated rat spleen cells. Alternatively, the use of highly cross-reactive ring-necked pheasant lysozyme in the cultures allowed expression of efficient help, ruling out any inherent deficiency in the T cells. The antibody response was specific and required MHC compatibility between the T lines and responding B cells. By using (H-2b X H-2d)F1 B cells and another H-2d-restricted HEL-specific T line, it was shown that only the H-2b-restricted T-B collaboration required exogenous factors, and the H-2d-restricted collaboration did not. Because both proliferative and helper responses are dependent upon MHC-restricted antigen presentation by macrophage-APC and B cells, respectively, these results suggest that the defect in the nonresponder H-2b-restricted T-B collaborative pathway may relate to the inability of B cells to adequately process and present HEL to clonal T cells.
D000818:Animals; D000941:Antigens / Q000276:immunology; D001402:B-Lymphocytes / Q000276:immunology*; D002460:Cell Line; D002645:Chickens; D002999:Clone Cells / Q000276:immunology; D003208:Concanavalin A / Q000502:physiology; D000939:Epitopes; D005260:Female; D006183:H-2 Antigens / Q000235:genetics; D008213:Lymphocyte Activation; D008211:Lymphocyte Cooperation; D008222:Lymphokines; D008297:Male; D051379:Mice; D008810:Mice, Inbred C57BL; D009113:Muramidase / Q000276:immunology; D006377:T-Lymphocytes, Helper-Inducer / Q000276:immunology*
D000941:Antigens; D000939:Epitopes; D006183:H-2 Antigens; D008222:Lymphokines; C021649:concanavalin A-induced helper factors; D003208:Concanavalin A; D009113:Muramidase