PROPORTIONAL AMPLIFICATION OF INDIVIDUAL HLA-A AND HLA-B ANTIGENS DURING UP-REGULATED EXPRESSION OF TOTAL CLASS-I HLA MOLECULES

Our recent studies demonstrated that each specific HLA-A or -B antigen is not expressed in equal quantity in cells of an individual and that the relative amounts of different HLA-A and -B antigens are genetical ly predetermined following Mendelian laws, These findings suggest the potential genetic importance of varied quantitative HLA expression on target cells in determining the sensitivity to cytotoxic T lymphocytes . It would be important to know whether the amounts of different HLA a ntigens ate differentially or proportionally amplified after upregulat ed expression of total HLA antigens. We have therefore determined the effects of IFN treatment, EBV transformation, and influenza virus infe ction on the quantitative expression of total HLA antigens and the rel ative quantities of different specific HLA-A and -B antigens in human fibroblast cell line and peripheral blood mononuclear leukocytes. In c ontrast to earlier studies using the transfected HLA genes, our result s show that different individual HLA-A and -B antigens are proportiona lly and not differentially amplified during upregulated expression of total class I HLA molecules. This finding indicates that the genetic p redetermination of varied quantitative expression of HLA antigens may play a role in influencing antiviral immunity and disease susceptibili ty.