Coexpression of the human HLA-A2 or HLA-B7 heavy chain gene and human beta 2-microglobulin gene in L cells.
L cells expressing human HLA-A2 or HLA-B7 class I antigen heavy chains are not recognized by human cytotoxic T lymphocytes directed at HLA-A2 or HLA-B7 antigens. To test whether the absence of human beta 2-m was the cause of the lack of recognition by the human cytotoxic T lymphocytes, coexpression of the human beta 2-m gene and the HLA-A2 or HLA-B7 heavy chain in L cells ("double transfectants") was obtained. In addition, L cells expressing HLA-A2 or HLA-B7 antigens in association with human beta 2-m were obtained by an exchange reaction, in which human beta 2-m from serum replaced the endogenous murine beta 2-m. Both types of transfectant cells were used in 51Cr-release assays and cold target inhibition assays for human cytotoxic T cell clones which were directed at HLA-A2 or HLA-B7. Neither human CTL clones nor a mixture of CTL specific for HLA-A2 and HLA-B7 were able to recognize these cells. Several alternative explanations for these observations are discussed.
D000818:Animals; D003602:Cytotoxicity, Immunologic; D005802:Genes, MHC Class II; D006680:HLA Antigens / Q000032:analysis / Q000235:genetics* / Q000276:immunology; D015789:HLA-A2 Antigen; D015793:HLA-B7 Antigen; D006801:Humans; D007143:Immunoglobulin Heavy Chains / Q000032:analysis / Q000235:genetics; D007739:L Cells / Q000276:immunology*; D051379:Mice; D013602:T-Lymphocytes, Cytotoxic / Q000276:immunology; D001613:beta 2-Microglobulin / Q000032:analysis / Q000235:genetics*
D006680:HLA Antigens; D015789:HLA-A2 Antigen; D015793:HLA-B7 Antigen; D007143:Immunoglobulin Heavy Chains; D001613:beta 2-Microglobulin