title: Cloned Listeria monocytogenes specific non-MHC-restricted Lyt-2+ T cells with cytolytic and protective activity.
abstract: Mice were infected with Listeria monocytogenes and Lyt-2+ T cell clones capable of lysing Ag-primed bone marrow macrophages were established. In accordance with earlier findings obtained at the population level, some T cell clones were identified which lysed bone marrow macrophages of different MHC type provided the relevant Ag was present. This unusual target cell recognition was further analyzed using a T3+, L3T4-, Lyt-2+, F23+, KJ16+ T cell clone, designated L-28. Target cell lysis by this clone was Ag specific, apparently non-MHC restricted. In contrast, YAC cells and P815 cells were not lysed by clone L-28. However, lysis of irrelevant targets could be induced by anti-T3, F23, or KJ16 mAb. Furthermore, Ag-specific lysis was blocked by anti-Lyt-2 mAb and by F(ab)2 fragments of F23 mAb. In addition to its cytolytic activity, clone L-28 produced IFN-gamma after co-stimulation with accessory cells, Ag, and rIL-2 and conferred significant protection on recipient mice when given together with rIL-2. These data suggest that non-MHC-restricted Lyt-2+ killer cells generated during listeriosis are cytolytic T lymphocytes that interact with their target Ag via the T cell receptor/T3 complex and the Lyt-2 molecule and, furthermore, that these cells play a role in anti-listerial resistance. The possible relevance of IFN-gamma secretion and target cell lysis for antibacterial protection is discussed.
mesh_terms: D000818:Animals; D000911:Antibodies, Monoclonal / Q000276:immunology; D000950:Antigens, Ly / Q000032:analysis; D002999:Clone Cells; D003602:Cytotoxicity, Immunologic; D007371:Interferon-gamma / Q000378:metabolism; D007694:Killer Cells, Natural / Q000276:immunology; D008089:Listeria monocytogenes / Q000276:immunology*; D008285:Major Histocompatibility Complex; D051379:Mice; D011948:Receptors, Antigen, T-Cell / Q000276:immunology; D013601:T-Lymphocytes / Q000276:immunology*; D013602:T-Lymphocytes, Cytotoxic / Q000276:immunology
chemical_list: D000911:Antibodies, Monoclonal; D000950:Antigens, Ly; D011948:Receptors, Antigen, T-Cell; D007371:Interferon-gamma