title: Regulation of T15 idiotype dominance. III. Phosphocholine-specific B-cell activation in vivo requires major histocompatibility complex-restricted T-cell help.
abstract: We have examined the requirement for major histocompatibility complex (MHC)-restricted T-cell help in the secondary in vivo antibody response to phosphocholine (PC). The memory response to PC has been demonstrated previously to be comprised of T15-dominant IgM and IgG3 plaque-forming cells (PFC) derived primarily from the Lyb-5+ B-cell subset, and IgG1 and IgG2 PFC, few of which bear the T15 idiotype and are predominantly derived from the Lyb-5- B-cell subset. Using carrier-primed (A X B)F1 T cells which have matured in a parentA chimeric environment so that "self" recognition is of the MHC determinants of parentA but not parentB, we have found that parentA PC-primed B cells, but not parentB PC-primed B cells, are activated. Even in the presence of an ongoing parentA anti-PC response, parentB PC-primed B cells were not activated, indicating that the restriction was between the helper T cell and the B cell, not between T-helper and accessory cells. MHC-restricted T-cell help was required by B cells producing T15+ and T15- IgM, IgG3, IgG1, and IgG2 responses.
mesh_terms: D000818:Animals; D000944:Antigens, Differentiation, B-Lymphocyte; D000954:Antigens, Surface / Q000276:immunology; D001402:B-Lymphocytes / Q000187:drug effects / Q000276:immunology*; D002460:Cell Line; D002794:Choline / Q000031:analogs & derivatives*; D007130:Immunoglobulin Idiotypes / Q000276:immunology*; D007156:Immunologic Memory; D008213:Lymphocyte Activation / Q000187:drug effects*; D008285:Major Histocompatibility Complex; D051379:Mice; D008810:Mice, Inbred C57BL; D008815:Mice, Inbred Strains; D010767:Phosphorylcholine / Q000494:pharmacology*; D006377:T-Lymphocytes, Helper-Inducer / Q000276:immunology*
chemical_list: D000944:Antigens, Differentiation, B-Lymphocyte; D000954:Antigens, Surface; D007130:Immunoglobulin Idiotypes; D010767:Phosphorylcholine; D002794:Choline