title: The asymmetry in idiotype-isotype expression in the response to phosphocholine is due to divergence in the expressed repertoires of Lyb-5+ and Lyb-5- B cells.
abstract: The X-linked CBA/N immune defect was used to investigate the roles of Lyb-5- and Lyb-5+ B cells in the memory response to PC-KLH (phosphocholine-conjugated keyhole limpet hemocyanin). (CBA/N X BALB/c)F1 (CB) male mice express the xid mutation and thereby lack the Lyb-5+ B cell subset, whereas their female littermates are normal and express both Lyb-5+ and Lyb-5- B cells. After priming with PC-conjugated hemocyanin (PC-Hy) in complete Freund's adjuvant, female B cells produce three phenotypic sets of PC-KLH-specific antibody. The first set (group I) is dominated by T15+, IgM, IgA, and IgG3, PC-specific antibodies. The second subset (group II) is specific for phenylphosphocholine (PPC), and is dominated by T15-, IgG1, and IgG2 antibodies. The third set (group III) recognizes an epitope(s) composed of both the PPC hapten and carrier determinants. PC-Hy-primed B cells from immune defective CB male mice produce the same number of IgG1 and IgG2 plaque-forming cells (PFC) as do PC-Hy-primed normal female cells, and these PFC are also predominantly T15- and PPC specific (group II). In addition, a significant amount of group III IgG1 and IgG2 antibody is observed in the immune defective male response. In contrast to female B cells, immune defective male B cells produce a low IgM, IgA, and IgG3 memory response that is not composed of PC-specific (group I) antibodies; in fact, most of these antibodies arise from group III precursors and are not inhibited by either PC or PPC. PC-specific antibodies usually represent less than 25% of the anti-PC-KLH response in immune defective mice; however, these PC-specific antibodies are predominantly T15-. These data suggest that the Lyb-5-B cells in both normal and immune defective mice produce the T15-, IgG1, and IgG2 antibodies that dominate the secondary immune response to PC-KLH, and that the Lyb-5+ B cells produce the T15+, IgM, IgA, and IgG3 portion of the secondary response in normal mice. This hypothesis was confirmed by priming normal mice with the R36a strain of Streptococcus pneumoniae or with PC-Hy in saline. These forms of PC-antigen prime only the Lyb-5+ B cell subset. The adoptive transfer of these two B cell sources results in an anti-PC-KLH response that is T15 dominant and totally PC inhibitable.(ABSTRACT TRUNCATED AT 400 WORDS)
mesh_terms: D000818:Animals; D000941:Antigens / Q000276:immunology; D000950:Antigens, Ly / Q000235:genetics* / Q000276:immunology; D001402:B-Lymphocytes / Q000145:classification / Q000276:immunology*; D005260:Female; D006433:Hemocyanins; D007116:Immunization, Passive; D007126:Immunoglobulin Allotypes / Q000032:analysis* / Q000235:genetics / Q000276:immunology; D007130:Immunoglobulin Idiotypes / Q000032:analysis* / Q000235:genetics / Q000276:immunology; D007153:Immunologic Deficiency Syndromes / Q000235:genetics / Q000276:immunology; D007156:Immunologic Memory; D008297:Male; D051379:Mice; D008815:Mice, Inbred Strains; D010767:Phosphorylcholine / Q000276:immunology; D006377:T-Lymphocytes, Helper-Inducer / Q000276:immunology
chemical_list: D000941:Antigens; D000950:Antigens, Ly; D007126:Immunoglobulin Allotypes; D007130:Immunoglobulin Idiotypes; D010767:Phosphorylcholine; D006433:Hemocyanins; C032808:keyhole-limpet hemocyanin