title: Mouse antibody response to group A streptococcal carbohydrate.
abstract: In an attempt to more fully understand the generation of antibody diversity to carbohydrate (CHO) Ag, we produced and characterized a panel of hybridoma cell lines specific for group A streptococcal CHO from mice injected with the intact bacteria (minus the hyaluronic acid capsule and cell wall protein Ag). We have analyzed the use of H and L chain V region genes in the early (day 7) and late response (hyperimmune) and have sequenced the dominant VH gene used in several of our hybridomas. Our data allowed us to assess the extent to which the recombination of various V, D, and J gene segments and somatic mutation contribute to antibody diversification in this system. In this report we confirm that a minimum of two VH and four VK gene segments are used to encode this response. We extend this analysis to show that multiple D and J gene segments are used and that a significant amount of junctional variability is tolerated in CDR 3. Our results indicate that the level of somatic mutation in the hyperimmune response is generally low in comparison with the response to haptens and protein Ag. These data also suggest that there is a positive selection for mutation in CDR 1 during the hyperimmune response to group A streptococcal CHO.
authors.affiliation: Department of Molecular Genetics and Microbiology, University of Massachusetts Medical School, Worcester 01655.
authors.forename: C D
authors.initials: CD
authors.lastname: Jarvis
authors.forename: L E
authors.initials: LE
authors.lastname: Cannon
authors.forename: J
authors.initials: J
authors.lastname: Stavnezer
mesh_terms: D000595:Amino Acid Sequence; D000818:Animals; D000907:Antibodies, Bacterial / Q000096:biosynthesis*; D001483:Base Sequence; D002460:Cell Line; D005803:Genes, Immunoglobulin; D006825:Hybridomas / Q000378:metabolism; D007143:Immunoglobulin Heavy Chains / Q000096:biosynthesis / Q000235:genetics; D007135:Immunoglobulin Variable Region / Q000096:biosynthesis / Q000235:genetics; D007145:Immunoglobulin kappa-Chains / Q000096:biosynthesis / Q000235:genetics; D051379:Mice; D008805:Mice, Inbred A; D008807:Mice, Inbred BALB C; D008969:Molecular Sequence Data; D011135:Polysaccharides, Bacterial / Q000276:immunology*; D013297:Streptococcus pyogenes / Q000276:immunology*; D013601:T-Lymphocytes / Q000378:metabolism
chemical_list: D000907:Antibodies, Bacterial; D007143:Immunoglobulin Heavy Chains; D007135:Immunoglobulin Variable Region; D007145:Immunoglobulin kappa-Chains; D011135:Polysaccharides, Bacterial; C044260:streptococcal group A cell wall carbohydrate