title: Cytotoxic factor produced by human blood lymphocytes of low density upon exposure to autologous B cells.
abstract: The mechanism of cytolysis by natural killer cells has been shown to involve a soluble lytic factor - the natural killer cytotoxic factor (NKCF). We have investigated the generation of NKCF on exposure of subpopulations of human blood lymphocytes to autologous B lymphocytes and EBV infected B lymphocytes (BEBV), and the sensitivity of these lymphocytes to the cytotoxic factor. We present evidence that the low density lymphocytes representing majority of NK cells, can be stimulated to produce NKCF by the autologous B/BEBV cells. Allogeneic B/BEBV cells did not induce NKCF production. Recognition of the autologous B/BEBV cells did not seem to involve Dr antigens. Although the autologous B/BEBV cells could stimulate NKCF production, the NKCF was lytic only to K562 targets. The autologous B/BEBV cells could neither be lysed by the factor produced, nor could these cells absorb the factor.
mesh_terms: D000911:Antibodies, Monoclonal; D001402:B-Lymphocytes / Q000276:immunology*; D002472:Cell Transformation, Viral; D003602:Cytotoxicity, Immunologic; D003609:Dactinomycin / Q000494:pharmacology; D006684:HLA-DR Antigens; D004854:Herpesvirus 4, Human; D000949:Histocompatibility Antigens Class II / Q000276:immunology; D006801:Humans; D007111:Immunity, Cellular; D066298:In Vitro Techniques; D007694:Killer Cells, Natural / Q000276:immunology*; D055646:Killer Factors, Yeast; D014176:Protein Biosynthesis; D011506:Proteins
chemical_list: D000911:Antibodies, Monoclonal; D006684:HLA-DR Antigens; D000949:Histocompatibility Antigens Class II; D055646:Killer Factors, Yeast; D011506:Proteins; D003609:Dactinomycin