Superantigen-dependent, cell-mediated cytotoxicity inhibited by MHC class I receptors on T lymphocytes.
Bacterial superantigens bind with high affinity to major histocompatibility complex (MHC) class II antigens on antigen-presenting cells and with T cell antigen receptor (TCR) beta chains on T lymphocytes, which results in the T cell activation responsible for toxic shock syndrome and food poisoning. Many cytotoxic T lymphocyte (CTL) clones were shown to have receptors for human leukocyte antigen (HLA) class I molecules that inhibited superantigen-induced cytotoxicity against appropriate class I-bearing target cells. One type of inhibitory receptor, NKB1, was present on CD4+ and CD8+TCR alpha beta+ CTL clones and blocked the killing of staphylococcal enterotoxin B (SEB)-coated targets bearing certain polymorphic HLA-B molecules. Expression of HLA-A, -B, and -C molecules on the SEB-coated targets also protected against cytolysis mediated by many NKB1-negative T cell clones, suggesting the presence of additional inhibitory MHC class I receptors. These HLA class I receptors may limit tissue destruction and possibly autoimmunity caused by activated T lymphocytes.
Phillips
J H
JH
Department of Human Immunology, DNAX Research Institute of Molecular and Cellular Biology, Palo Alto, CA 94304, USA.
Gumperz
J E
JE
Parham
P
P
Lanier
L L
LL
D000328:Adult; D003602:Cytotoxicity, Immunologic; D004768:Enterotoxins / Q000276:immunology; D015234:HLA-A Antigens / Q000276:immunology; D015235:HLA-B Antigens / Q000276:immunology; D015236:HLA-C Antigens / Q000276:immunology; D006801:Humans; D011948:Receptors, Antigen, T-Cell / Q000276:immunology*; D016693:Receptors, Antigen, T-Cell, alpha-beta / Q000276:immunology; D011971:Receptors, Immunologic / Q000276:immunology*; D054340:Receptors, KIR; D054341:Receptors, KIR3DL1; D018089:Superantigens / Q000276:immunology*; D013602:T-Lymphocytes, Cytotoxic / Q000276:immunology*; D014162:Transfection
D004768:Enterotoxins; D015234:HLA-A Antigens; D015235:HLA-B Antigens; D015236:HLA-C Antigens; D011948:Receptors, Antigen, T-Cell; D016693:Receptors, Antigen, T-Cell, alpha-beta; D011971:Receptors, Immunologic; D054340:Receptors, KIR; D054341:Receptors, KIR3DL1; D018089:Superantigens; C031818:enterotoxin B, staphylococcal