title: Generation of antibody diversity. IV. Variation within single clones of antibody-forming cells developing in vivo.
abstract: Previous experimental work demonstrated that clonal variation occurs in vitro. The present experiments were designed to test for clonal variation in vivo. B cells were transferred at limiting dilution, with antigen, into irradiated recipients. Seven days later spleens were assayed for plaque-forming cell (PFC) colonies. Control experiments showed that these PFC colonies were clones, that is, they were derived from a single B cell precursor. When the clones were analyzed for heterogeneity of the PFC population, using cross-reactivity on various mixtures of red blood cells as a method of detecting differences in antibody specificity, from 23-83% of the clones contained variants. By adjusting the amounts of helper activity and antigen available to a developing clone, we have been able to influence this variation; high levels of help and/or antigen favor pure clones, while low levels of either produce mainly mixed clones.
mesh_terms: D000276:Adjuvants, Immunologic; D000818:Animals; D000918:Antibody Specificity; D000921:Antibody-Producing Cells / Q000276:immunology*; D000941:Antigens; D002999:Clone Cells / Q000276:immunology*; D004912:Erythrocytes / Q000276:immunology; D005260:Female; D006649:Histocompatibility Antigens; D008297:Male; D051379:Mice; D008815:Mice, Inbred Strains; D011135:Polysaccharides, Bacterial / Q000276:immunology; D011828:Radiation Chimera; D013154:Spleen / Q000166:cytology / Q000276:immunology; D013601:T-Lymphocytes / Q000276:immunology
chemical_list: D000276:Adjuvants, Immunologic; D000941:Antigens; D006649:Histocompatibility Antigens; D011135:Polysaccharides, Bacterial