Cell-mediated lympholysis: examination of HLA genetic fine structure and complementation using cytotoxic lymphocytes

Human cytotoxic lymphocytes (CTL), sensitized in vitro in one-way mixed lymphocyte cultures between two unrelated individuals, have been used to study target cell determinants. One pair of CTL shows strong cell-mediated lympholysis responses against the specific target cells as well as against third-party target cells obtained from unrelated individuals. Testing of sixty target cells shows a significant association between the two CTL with a correlation coefficient of 0.67 in the panel. The target determinant recognized by the CTL is not an HLA-A,B,C or D specificity, as defined by standard serological and cellular reagents. Segregation studies in a large family reveal that the new specificity defined by the CTL is controlled by HLA, and its recognition may be restricted by the HLA complex.