title: Two functionally distinct subpopulations of human T cells that collaborate in the generation of cytotoxic cells responsible for cell-mediated lympholysis.
abstract: A human thymus-dependent differentiation antigen, TH2 was defined by a rabbit anti-human T cell serum absorbed with autologous B lymphoblasts and leukemic cells bearing T cell markers from a patient with chronic lymphocytic leukemia. Anti-TH2 reacted specifically with thymus-derived lymphoid cells and exhibited two distinct profiles of reactivity with normal peripheral T cells as detected by indirect immunofluorescence on a FACS I. Isolation of strongly reactive, TH2+, from weakly reactive, TH2- T cells by fluorescence-activated cell sorting revealed that the TH2+ subset contained most of the killer activity in cell-mediated lympholysis (CML), but had a diminished response in MLC and a suboptimal or negligible proliferative response to soluble antigens (mumps, PPD, tetanus toxoid). In contrast, the TH2- subset contained markedly less killer activity but amplified cytotoxicity by TH2+ cells and exhibited a proliferative response to both alloantigen and soluble antigens that was often significantly greater than the response by unseparated T cells. The relevance of these findings to previously described human T cell subsets and to functional subpopulations of murine T cells is discussed.
mesh_terms: D000042:Absorption; D000328:Adult; D000818:Animals; D001665:Binding Sites; D002469:Cell Separation; D003602:Cytotoxicity, Immunologic; D005455:Fluorescent Antibody Technique; D006801:Humans; D007111:Immunity, Cellular; D007519:Isoantigens; D007694:Killer Cells, Natural / Q000276:immunology; D008213:Lymphocyte Activation; D007959:Lymphocyte Culture Test, Mixed; D008875:Middle Aged; D011817:Rabbits; D013601:T-Lymphocytes / Q000276:immunology*
chemical_list: D007519:Isoantigens