title: Immunologic cytotoxicity against autologous human lymphocytes transformed or infected by Epstein-Bar virus: role of antibody-dependent cellular cytotoxicity in health individuals.
abstract: Immunologic cytotoxicity against lymphocytes transformed or infected by Epstein-Barr virus (EBV) was mainly studied in an autologous in vitro system by 51Cr release assay and EBV-determined nuclear antigen (EBNA)-specific trypan blue exclusion method. When the cells of newly established EBV-transformed or spontaneously transformed lines were incubated with unfractionated autologous healthy donor lymphocytes or T-cell-depleted lymphocytes in the presence of EBV-positive autologous or allogeneic serum, the transformed cells were killed with high frequency. Exposure to lymphocytes alone or to EBV-positive serum alone was not effective. The cytotoxic reaction was directed against cells positive for EBV-induced membrane antigens (MA) but not against MA-negative transformed cells. A very small fraction (1 of 200) of healthy donor lymp]hocytes exposed to EBV converted into EBNA-positive and MA-positive cells, and these were also killed by the remaining autologous lymphocytes in the presence of EBV-positive serum. These results indicated that the present cytotoxic reaction represents antibody-dependent cellular cytotoxicity (ADCC), and this particular mechanism probably plays an important role in the immunologic surveillance in the protection against EBV-induced oncogenesis in seropositive individuals. Such ADCC, however, does not seem to function effectively in patients with systemic lupus erythematosus.
mesh_terms: D000914:Antibodies, Viral / Q000276:immunology; D000920:Antibody-Dependent Cell Cytotoxicity; D000954:Antigens, Surface / Q000276:immunology; D000956:Antigens, Viral; D002460:Cell Line; D002472:Cell Transformation, Viral; D004854:Herpesvirus 4, Human / Q000276:immunology; D006801:Humans; D007074:Immunoglobulin G / Q000276:immunology; D008180:Lupus Erythematosus, Systemic / Q000276:immunology; D008213:Lymphocyte Activation; D008214:Lymphocytes / Q000276:immunology*
chemical_list: D000914:Antibodies, Viral; D000954:Antigens, Surface; D000956:Antigens, Viral; D007074:Immunoglobulin G