title: Frequency and specificity of precursors of interleukin 2-producing cells in nude mice.
abstract: The frequency and specificity of precursors of interleukin 2-producing cells (IL 2-P) in congenitally athymic (nude) N:NIH(s)II mice was investigated. IL 2-P were detected and quantitated in a sensitive limiting dilution microassay in which Lyt-2-depleted lymphoid cell populations were first cultured for 12 days with irradiated allogeneic (DBA/2) stimulating cells and a source of IL 2 and then washed and restimulated with irradiated T cell-depleted stimulating cells for an additional 24 hr. Supernatants from restimulated cultures were assayed for IL 2 activity on CTLL indicator cells, and IL 2-P frequencies were calculated. The results indicated that IL 2-P were undetectable in young (6-wk-old) nude mice, but increased in frequency with age to eventually reach levels five to 10-fold lower than their euthymic (nu/+) littermates. In specificity studies, microcultures established originally with limiting numbers of nude or nu/+ responding cells and DBA/2 stimulating cells were split into three aliquots and restimulated with T cell-depleted stimulating cells of DBA/2, BALB/c, or C57BL/6 origin. Analysis of IL 2 production in these restimulated microcultures clearly demonstrated different patterns of cross-reactivity in individual nude mice that were not seen in nu/+ controls. These results are discussed in the context of a model proposing that the T cell repertoire in athymic mice is oligoclonal in nature.
mesh_terms: D000375:Aging; D000818:Animals; D002452:Cell Count; D002478:Cells, Cultured; D003429:Cross Reactions; D003602:Cytotoxicity, Immunologic; D000939:Epitopes / Q000235:genetics; D007376:Interleukin-2 / Q000096:biosynthesis*; D008198:Lymph Nodes / Q000166:cytology / Q000502:physiology; D051379:Mice; D008807:Mice, Inbred BALB C; D008810:Mice, Inbred C57BL; D008811:Mice, Inbred DBA; D008819:Mice, Nude / Q000276:immunology*; D013154:Spleen / Q000166:cytology / Q000502:physiology; D013234:Stem Cells / Q000276:immunology*; D013601:T-Lymphocytes / Q000166:cytology / Q000276:immunology* / Q000502:physiology
chemical_list: D000939:Epitopes; D007376:Interleukin-2