title: Absence of allogeneic restriction in human T-cell-mediated cytotoxicity to Epstein-Barr virus-infected target cells. Demonstration of an HLA-linked control at the effector level.
abstract: Peripheral T lymphocytes from patients with infectious mononucleosis (IM) are sensitized in vivo against the Epstein-Barr virus (EBV). The expression of HLA-A, B, or C molecules at the target cell surface is necessary for the cytotoxic reaction because (a) EBV-positive Daudi cells lacking HLA-A, B, and C determinants are resistant to anti-EBV T-cell lysis, (b) cytolysis of EBV-positive target cells can be consistently inhibited by anti-HLA-A, B, and C and anti-beta 2 microglobulin antibodies. However, no evidence for allogeneic restriction in this system was apparent as (a) cytotoxic T lymphocytes (CTL) from one given individual could exert a cytotoxicity of a similar magnitude on different EBV-positive target cells, regardless of the number of HLA-A or B specificities shared by the effectors and targets; (b) CTL from IM patients were able to kill target cells without any HLA-A or B antigen in common; and (c) T5-1 variants lacking one or two HLA antigens at the A, B, or D locus are killed to the same extent as the parental cells. 7 of the 9 IM patients with detectable circulating anti-EBV CTL carried the HLA-A1 antigen, whereas none of the 16 IM patients lacking detectable peripheral CTL were HLA-A1 positive (mean specific lysis of T5-1 target cells by T cells from HLA-A1 positive patients: 29.3 vs. 0.6% in HLA-A1-negative patients) (P less than 10(-9)). These data suggest an HLA-A1-linked gene control of the magnitude of the anti-EBV CTL response. Thus, the HLA region appears to act at two different level sin the T-cell-mediated lysis of EBV-infected cells by controlling first, the development of anti-EBV and second, the expression of HLA-A, B, and C molecules involved as recognition structures at the target cell surface.
mesh_terms: D000937:Antigen-Antibody Reactions; D003602:Cytotoxicity, Immunologic; D005802:Genes, MHC Class II; D008040:Genetic Linkage; D006680:HLA Antigens / Q000235:genetics*; D004854:Herpesvirus 4, Human / Q000276:immunology*; D006801:Humans; D007111:Immunity, Cellular; D007244:Infectious Mononucleosis / Q000276:immunology*; D007518:Isoantibodies; D008285:Major Histocompatibility Complex; D013601:T-Lymphocytes / Q000276:immunology*; D001613:beta 2-Microglobulin / Q000276:immunology
chemical_list: D006680:HLA Antigens; D007518:Isoantibodies; D001613:beta 2-Microglobulin