title: Two loci in I-J subregion of the H-2 complex controlling molecules selectively expressed on suppressor and helper T cells.
abstract: Different batches of alloantiserum directed at the I-J subregion products of the H-2 major histocompatibility complex (anti-I-J) induced either suppression or augmentation of the in vitro secondary antibody response when added in a minute quantity to the culture of primed spleen cells. The suppressive or augmenting effect of the individual antiserum was found to be determined by its predominant specificity for either one of the two different molecules, both encoded in the I-J subregion, that were selectively expressed on functionally different subsets of T cells, i.e., suppressor (Ts) and helper (Th2) T cells. This was determined by the differential absorption of antiserum with Lyt-1+ and Lyt-2+ T cells as well as with suppressor hybridomas that express an I-Jk product. It was found that the absorption of an anti-I-J antiserum with Lyt-1+ T cells resulted in the loss of activity to eliminate a set of helper T cells (Th2) while leaving the ability to affect antigen-specific suppressor T cells (Ts). The absorption of the same antiserum with either Lyt-2+ T cells or suppressor hybridomas eliminated the activity to kill Ts but not Th2. Thus, the results indicate that the I-J subregion accommodates two or more loci that code for discrete molecules expressed on functionally different subsets of T cells. Because the simple addition of a minute quantity of antisera to the culture resulted in the modulation of antibody response presumably by affecting these two sets of T cells, it is suggested that I-J subregion products act as functional molecules in regulatory cell interactions.
mesh_terms: D000818:Animals; D000918:Antibody Specificity; D000950:Antigens, Ly / Q000235:genetics / Q000276:immunology; D000961:Antilymphocyte Serum / Q000145:classification / Q000494:pharmacology; D002874:Chromosome Mapping; D003602:Cytotoxicity, Immunologic; D006183:H-2 Antigens / Q000235:genetics; D006238:Haploidy; D000949:Histocompatibility Antigens Class II / Q000145:classification / Q000235:genetics*; D006825:Hybridomas / Q000276:immunology; D007117:Immunization, Secondary; D051379:Mice; D008809:Mice, Inbred C3H; D008810:Mice, Inbred C57BL; D013601:T-Lymphocytes / Q000145:classification / Q000276:immunology*; D050378:T-Lymphocytes, Regulatory / Q000276:immunology*
chemical_list: D000950:Antigens, Ly; D000961:Antilymphocyte Serum; D006183:H-2 Antigens; D000949:Histocompatibility Antigens Class II