HLA-A2 as a target for cell-mediated lympholysis: evidence from immunoselected HLA-A2 negative mutant cell lines.
Cloned mutants of the human B lymphoblastoid cell line SB have been isolated using mutagenesis with ethyl methanesulfonate followed by negative selection with an anti-HLA-A2 serum and complement. Absorption analysis with 125I Staphylococcus aureus protein A binding to antibody sensitized cells. HLA typing, and immune precipitation analysis showed the mutants to be serologically identical to the SB parent except for the loss of HLA-A2. When tested as target cells for cell-mediated lympholysis by cytotoxic T lymphocytes generated in the mixed lymphocyte response, the SB and mutant cell lines demonstrated comparable susceptibility when the putative targets were HLA antigens other than HLA-A2. However, when compared for susceptibility to lysis by cytotoxic T lymphocytes considered to be HLA-A2 specific, the SB parent was effectively killed whereas little or no killing of the HLA-A2 mutants was observed. The results provide a new line of evidence that HLA antigens recognized by antibody can also be the true molecular targets for cytotoxic T lymphocytes.
D000042:Absorption; D000818:Animals; D001666:Binding Sites, Antibody; D002460:Cell Line; D011232:Chemical Precipitation; D003602:Cytotoxicity, Immunologic; D006680:HLA Antigens / Q000276:immunology*; D006650:Histocompatibility Testing; D006801:Humans; D007111:Immunity, Cellular; D009154:Mutation; D011817:Rabbits; D013205:Staphylococcal Protein A / Q000378:metabolism
D006680:HLA Antigens; D013205:Staphylococcal Protein A