title: Major histocompatibility complex-restricted augmenting T cells induced by in vitro cultivation of antigen-primed T cells. A new parallelism between suppressor and augmenting circuits.
abstract: In vitro cultivation of primed T cells with antigen resulted in the induction of a regulatory T cell that nonspecifically augmented the in vitro antibody responses of H-2-compatible T and B cells. This T cell, designated as the augmenting T cell (Ta), was unable to help B cells by itself but enhanced the antibody response of B cells to several multitudes only when conventional helper T (Th) cells or cloned Th cells from the same H-2 haplotype coexisted. Ta was radioresistant and belonged to Lyt-1+, 2-, L3T4+, I-J- T cell lineage. Ta exhibited interesting H-2-restricted activities: when primed T cells from (A X B) F1 were cultured with the antigen in the presence of parent A type antigen-presenting cells, the induced Ta was able to augment the antibody response of (A x B) F1 B cells in the presence of Th cells from F1----A but not from F1----B radiation bone marrow chimeras. This indicates that the induction of Ta in an F1 T cell population is dependent on the H-2 haplotype of antigen-presenting cells during in vitro cultivation. The restriction specificity of the established Ta is, however, not directed to the class II antigen itself but to the restriction specificity of Th cells that recognize class II antigen. In support of this is the fact that the elimination of A-restricted Th cells during cultivation by treatment with anti-I-J mAb, which is known to react with H-2-restricted Th cells, resulted in failure of induction of Ta cells having the augmenting activity for the A-restricted response.
mesh_terms: D000818:Animals; D000917:Antibody Formation; D000938:Antigen-Presenting Cells / Q000276:immunology; D002478:Cells, Cultured; D006183:H-2 Antigens / Q000276:immunology*; D000949:Histocompatibility Antigens Class II / Q000276:immunology; D008211:Lymphocyte Cooperation; D051379:Mice; D008815:Mice, Inbred Strains / Q000276:immunology; D011828:Radiation Chimera; D011836:Radiation Tolerance; D013601:T-Lymphocytes / Q000145:classification / Q000276:immunology* / Q000528:radiation effects; D050378:T-Lymphocytes, Regulatory / Q000276:immunology / Q000528:radiation effects
chemical_list: D006183:H-2 Antigens; D000949:Histocompatibility Antigens Class II; C043911:I-J-antigen