Activation of autologous reactive helper T lymphocytes for differentiation of human B lymphocytes.
We present experimental evidence that autologous reactive T cells are triggered to proliferate by HLA-D or Ia-like antigens on pokeweed mitogen-pulsed non-T cells and that a subpopulation of these proliferating cells in turn helps PWM-primed B cells to differentiate into immunoglobulin-secreting cells. These helper T cells displayed a proliferation kinetics different from that of other autologous reactive T cells in peaking on the second day of culture and were relatively resistant to irradiation or treatment with mitomycin C. Since heterologous anti-Ia antibody (F(ab')2 reagent) inhibits proliferation of helper T cells and the generation of plaque-forming cells, Ia antigen is an essential component in PWM-stimulated B cell differentiation. Anti-Ia reagent was shown to interfere with B cell differentiation in 2 ways. First, it abrogates the ability of PWM-primed non-T cells to activate helper T cells. Second, it directly affects a differentiation of B cells into Ig-secreting cells even in the presence of the activated helper T cells.
D000818:Animals; D000921:Antibody-Producing Cells / Q000276:immunology; D001402:B-Lymphocytes / Q000166:cytology*; D002454:Cell Differentiation; D006462:Hemolytic Plaque Technique; D000949:Histocompatibility Antigens Class II / Q000276:immunology; D006801:Humans; D008213:Lymphocyte Activation; D008937:Mitomycins / Q000494:pharmacology; D011043:Pokeweed Mitogens / Q000494:pharmacology; D012397:Rosette Formation; D012756:Sheep; D013601:T-Lymphocytes / Q000145:classification / Q000276:immunology*
D000949:Histocompatibility Antigens Class II; D008937:Mitomycins; D011043:Pokeweed Mitogens