title: Lymphocyte-mediated cytotoxicity against tumor cells specificity and characterization of concanavalin A-activated cytotoxic effector lymphocytes.
abstract: The selective T cell mitogen Con A was found to induce cytotoxic effectorlymphocytes after in vivo or in vitro treatment. The effector cells exhibited immunologic specificity when tested against tumor cells, killing targets only across H-2 histocompatibility barriers. Thus, Con A caused a polyclonal T cell activation, resulting in the appearance of effector cells capable of recognizing all H-2 antigens, except those coded for by the major histocompatibility loci of the lymphocyte donor. These experiments demonstrate that Con A is capable of activating pre-existing T cells to reveal their genetically determined immunological specificity, and furthermore suggest that there is a deletion of T cell clones with specificity for self. The activated effector cells were characterized as T blasts being relatively insensitive to treatment with anti-O serum plus complement. The precursors of the Con A-activated effector cells were shown to reside primarily in the spleen, to be radio-resistant up to 400 R, and to be short-lived after adult thymectomy. Thus, the population of T cells capable of activation to cytotoxic effector lymphocytes by Con A has similar physical characteristics to the splenic subset(s) of T cells mediating both GVH and cytotoxicity responses upon alloimmunization.
mesh_terms: D000818:Animals; D002460:Cell Line; D002462:Cell Membrane / Q000276:immunology; D002999:Clone Cells; D003208:Concanavalin A / Q000494:pharmacology*; D003601:Cytotoxicity Tests, Immunologic; D004247:DNA / Q000096:biosynthesis; D000939:Epitopes; D006649:Histocompatibility Antigens; D008213:Lymphocyte Activation / Q000187:drug effects*; D051379:Mice; D008815:Mice, Inbred Strains; D009374:Neoplasms, Experimental / Q000276:immunology*; D011830:Radiation Effects; D013154:Spleen / Q000187:drug effects / Q000378:metabolism / Q000528:radiation effects; D013601:T-Lymphocytes / Q000187:drug effects / Q000276:immunology*
chemical_list: D000939:Epitopes; D006649:Histocompatibility Antigens; D003208:Concanavalin A; D004247:DNA