title: Regulation of clones responding to dextran B1355S. II. Response of T-dependent and T-independent precursors.
abstract: The existence of precursors for TI and TD alpha 1 leads to 3 dextran antigens in BALB/c mice was demonstrated. A T-dependent dextran antigen was prepared by coupling dextran B1355S to hemocyanin and subsequent digestion with dextranase. The PFC response of BALB/c mice primed with hemocyanin to dextran-hemocyanin was found to be 8 times higher than in unprimed animals. The splenic focus assay was adapted for the analysis of precursors responding to T-dependent and T-independent dextran antigens. Pretreatment of recipients with anti-thymocyte serum abolished the response in fragment cultures to dextran-hemocyanin but did not affect the response to dextran B1355S. The frequencies of precursors in the adult BALB/c mouse responding to dextran and dextran-hemocyanin were determined by limiting dilution analysis. The frequency of T-dependent precursors was found to be almost 3 times greater than the frequency of T-independent precursors.
mesh_terms: D000818:Animals; D000918:Antibody Specificity; D000941:Antigens; D001402:B-Lymphocytes / Q000166:cytology; D002454:Cell Differentiation; D002478:Cells, Cultured; D002999:Clone Cells / Q000276:immunology; D003911:Dextrans / Q000276:immunology*; D005260:Female; D008040:Genetic Linkage; D008297:Male; D051379:Mice; D008807:Mice, Inbred BALB C; D011817:Rabbits; D013601:T-Lymphocytes / Q000276:immunology*
chemical_list: D000941:Antigens; D003911:Dextrans