title: Activation of abundant precursors associated with the response of Mlsa H-2k spleens to Mlsc antigen.
abstract: We have determined the frequency of splenic interleukin 2-producing T-cell precursors that respond to H-2-identical, Mls-disparate stimulating cells. Gene products of the Mlsa and Mlsd alleles are highly stimulatory in primary mixed lymphocyte reactions and activate substantial numbers of T-cell precursors in normal spleens. Although the product of the Mlsc allele has been described as weakly stimulatory in primary mixed lymphocyte reactions, we detected abundant T-cell precursors responsive to Mlsc under our limiting dilution conditions; H-2k Mlsa T-cell precursors responding to Mlsc were as frequent (2.605 per 1000) as H-2k Mlsb or Mlsc T-cells responsive to Mlsd (1.975 per 1000). In contrast, using the frequency of self-responding cells as a threshold, we were unable to detect precursors for Mlsa, Mlsb, Mlsc, or Mlsd in H-2b mice, for Mlsb in H-2k mice, or for Mlsc in H-2k Mlsb or Mlsd mice. Thus, we conclude that in select strain combinations and under our experimental conditions Mlsc stimulators can activate T-cell precursors that are as abundant as precursors reactive to strong stimulators Mlsa and Mlsd.
mesh_terms: D000483:Alleles; D000818:Animals; D000954:Antigens, Surface / Q000235:genetics / Q000276:immunology*; D006183:H-2 Antigens / Q000276:immunology*; D006412:Hematopoietic Stem Cells / Q000276:immunology; D000949:Histocompatibility Antigens Class II / Q000276:immunology; D066298:In Vitro Techniques; D007376:Interleukin-2 / Q000096:biosynthesis; D008213:Lymphocyte Activation; D007959:Lymphocyte Culture Test, Mixed; D051379:Mice; D008815:Mice, Inbred Strains; D016747:Minor Lymphocyte Stimulatory Antigens; D013045:Species Specificity; D013154:Spleen / Q000276:immunology*; D013601:T-Lymphocytes / Q000276:immunology*
chemical_list: D000954:Antigens, Surface; D006183:H-2 Antigens; D000949:Histocompatibility Antigens Class II; D007376:Interleukin-2; D016747:Minor Lymphocyte Stimulatory Antigens