title: Interaction of helper T cells and Lyb5+ B cells responding to phosphorylcholine is MHC-restricted.
abstract: The requirements for T cell/B cell interaction for the induction of primary in vitro antibody responses to phosphorylcholine (PC)-keyhole limpet hemocyanin (KLH) were examined. Long-term helper T cell lines derived from KLH-primed (CBA/N X BALB/c) F1 female mice (H-2k/d) were able to support a T15-idiotype dominant, IgM anti-PC response of BALB/c (H-2d) B cells and macrophages, but could not activate PC-specific responses by BALB.B (H-2b) B cells, even in the presence of irradiated H-2k/d antigen-presenting cells. Polyclonal IgM secretion in the same cultures did not appear to depend upon a major histocompatibility complex (MHC)-restricted T-B interaction. Since IgM anti-PC responses seem to be entirely derived from the Lyb5+ B cell subpopulation, we conclude that at least some Lyb5+ B cells can only be activated by MHC-restricted T-B interactions. We also found that xid B cells from (CBA/N X BALB/c) F1 male mice could be polyclonally activated by helper T cell lines by an apparently MHC-unrestricted interaction. Our data thus suggests that residence in the Lyb5- or Lyb5+ B cell subset does not determine the T:B interaction requirements for antibody synthesis.
mesh_terms: D000818:Animals; D000950:Antigens, Ly / Q000276:immunology*; D001402:B-Lymphocytes / Q000145:classification / Q000276:immunology*; D002794:Choline / Q000031:analogs & derivatives*; D000939:Epitopes; D005260:Female; D006183:H-2 Antigens / Q000235:genetics; D006433:Hemocyanins / Q000276:immunology; D007075:Immunoglobulin M / Q000096:biosynthesis; D008211:Lymphocyte Cooperation; D008297:Male; D051379:Mice; D008807:Mice, Inbred BALB C; D010767:Phosphorylcholine / Q000276:immunology*; D006377:T-Lymphocytes, Helper-Inducer / Q000276:immunology*
chemical_list: D000950:Antigens, Ly; D000939:Epitopes; D006183:H-2 Antigens; D007075:Immunoglobulin M; D010767:Phosphorylcholine; D006433:Hemocyanins; C032808:keyhole-limpet hemocyanin; D002794:Choline