title: Immunoregulation in the rat: characteristics of a suppressor T cell that inhibits antigen-dependent cell proliferation.
abstract: We have examined the characteristics of a rat suppressor T cell (Ts) that inhibited the antigen-dependent proliferative response of antigen-primed T cells. The kinetics of in vitro induction of Ts from lymph node T cells obtained from antigen-primed rats indicated that Ts were induced in the presence of the priming antigen within 48 hr of culturing. The Ts produced during the first 48 hr of in vitro cultures were radiosensitive (2000 rad) but became partially radioresistant within the next 48 hr of culturing. In the presence but not the absence of priming antigen, Ts inhibited the antigen-dependent proliferative response to the priming antigen as well as to heterologous antigens. Suppression appeared to be mediated via a nondialyzable suppressor factor (TsF). The induction of Ts in cultures required the presence of OX-6-/OX-8- T cells, antigen-presenting cells, and the antigen. Although a majority of cells recovered from the induced cultures were OX-8+, there was no evidence that OX-8+ antigen expression per se was related to Ts activity. Addition of highly purified IL 2 augmented the Ts-mediated suppression. The immunoregulatory implications of these findings are discussed.
authors.forename: M L
authors.initials: ML
authors.lastname: Sopori
authors.forename: R S
authors.initials: RS
authors.lastname: Perrone
authors.forename: S
authors.initials: S
authors.lastname: Cherian
authors.forename: R J
authors.initials: RJ
authors.lastname: Cross
authors.forename: A M
authors.initials: AM
authors.lastname: Kaplan
mesh_terms: D000818:Animals; D000939:Epitopes; D000949:Histocompatibility Antigens Class II; D007376:Interleukin-2 / Q000502:physiology; D007700:Kinetics; D008213:Lymphocyte Activation / Q000528:radiation effects; D008222:Lymphokines / Q000502:physiology; D010641:Phenotype; D051381:Rats; D011916:Rats, Inbred F344 / Q000276:immunology*; D011919:Rats, Inbred Strains / Q000276:immunology*; D013491:Suppressor Factors, Immunologic; D050378:T-Lymphocytes, Regulatory / Q000145:classification* / Q000276:immunology / Q000528:radiation effects; D013997:Time Factors
chemical_list: D000939:Epitopes; D000949:Histocompatibility Antigens Class II; D007376:Interleukin-2; D008222:Lymphokines; D013491:Suppressor Factors, Immunologic