title: Contribution of Lyb 5+ and Lyb 5- B cells to the primary and secondary phosphocholine-specific antibody response.
abstract: Due to a mutation on their X-chromosome, CBA/N mice lack the Lyb-5+ subset of B cells. The loss of this B cell subset results in a profound alteration in the immune response of these mice to the hapten phosphocholine (PC). Thus, when these mice are immunized with high doses of PC-KLH (200 micrograms) in CFA, they: 1) fail to produce IgM anti-PC antibodies; 2) produce little or no anti-PC antibody bearing the normally predominant T15-idiotype; and 3) produce IgG anti-PC antibodies only late in the primary response. In order to more fully delineate this defect in responsiveness to PC, the splenic focus assay was used to analyze Lyb-5- B cell precursors from both normal and immune defective mice. Lyb-5- cells were obtained from normal (CBA/N x DBA/2)F1 (CD) female spleens by treatment with anti-Lyb-5 serum and complement. These normal Lyb-5- cells and Lyb-5- cells from immune defective CD male mice were stimulated in vitro with either PC-Hy or TNP-Hy in the presence of Hy-primed T helper cells. The results demonstrate that primary Lyb-5- PC-specific B cells fail to respond in the splenic focus assay, while secondary Lyb-5- PC-specific precursors respond normally, and that both primary and secondary Lyb-5- TNP-specific precursors respond in the splenic focus assay. These data suggest that Lyb-5- PC-specific precursors must differentiate into memory cells before they can be activated to secrete antibody, and they also indicate that the Lyb-5- B cell subset may be composed of two subsets with different activation requirements.
mesh_terms: D000818:Animals; D000917:Antibody Formation; D000950:Antigens, Ly / Q000235:genetics / Q000276:immunology*; D001402:B-Lymphocytes / Q000145:classification* / Q000276:immunology; D002794:Choline / Q000031:analogs & derivatives*; D005260:Female; D006412:Hematopoietic Stem Cells / Q000276:immunology; D007117:Immunization, Secondary; D007130:Immunoglobulin Idiotypes / Q000096:biosynthesis / Q000235:genetics; D007075:Immunoglobulin M / Q000096:biosynthesis; D008213:Lymphocyte Activation; D008297:Male; D051379:Mice; D008807:Mice, Inbred BALB C; D008808:Mice, Inbred CBA; D008811:Mice, Inbred DBA; D010767:Phosphorylcholine / Q000276:immunology*; D011817:Rabbits; D013154:Spleen / Q000166:cytology
chemical_list: D000950:Antigens, Ly; D007130:Immunoglobulin Idiotypes; D007075:Immunoglobulin M; D010767:Phosphorylcholine; D002794:Choline