title: Suppression of cytotoxic lymphocyte responses in vitro by soluble products of alloantigen-activated spleen cells.
abstract: Suppression of in vitro cytotoxic lymphocyte (CL) responses was mediated by soluble factor(s) produced when in vivo alloantigen-activated suppressor cells were re-exposed to alloantigen in vitro. Elaboration of suppressor factor (SF) was T cell dependent and was optimal 7 days after alloantigen injection. Suppressor factor failed to inhibit CL generation when alloantigen-primed cells rather than normal spleen cells were used as responders. Moreover, SF added at day 3 of incubation rather than at culture initiation was also ineffective, suggesting that suppression probably occurs during antigen induction or early differentiation. Additionally, suppression was abrogated by the presence of 2-mercaptoethanol. Studies combining SF and CL responder cells from a variety of H-2 disparate mouse sdrains revealed that suppression of CL responses: 1) was not alloantigen specific; 2) did not require H-2 homology between responder and suppressor strains; and 3) could not be demonstrated with CBA/J mice. Although CBA/J CL responses were not suppressed by any SF preparation, allo-sensitized CBA/J spleen cells did elaborate SF that inhibited BALB/c CL responses.
mesh_terms: D000818:Animals; D002478:Cells, Cultured; D003602:Cytotoxicity, Immunologic; D006649:Histocompatibility Antigens / Q000235:genetics; D007519:Isoantigens; D007959:Lymphocyte Culture Test, Mixed; D008214:Lymphocytes / Q000276:immunology*; D008623:Mercaptoethanol / Q000494:pharmacology; D051379:Mice; D008807:Mice, Inbred BALB C; D008809:Mice, Inbred C3H; D008810:Mice, Inbred C57BL; D008808:Mice, Inbred CBA; D008811:Mice, Inbred DBA; D012995:Solubility; D013154:Spleen / Q000276:immunology*; D013601:T-Lymphocytes / Q000276:immunology*; D013997:Time Factors
chemical_list: D006649:Histocompatibility Antigens; D007519:Isoantigens; D008623:Mercaptoethanol