Immunological features of juvenile onset diabetic patients correlated to HLA type.

Ninety-six juvenile onset type diabetics showed an increase in the frequency of HLA B8 and B15 and a decrease in frequency of HLA B7 antigens. Sixty-four maturity onset diabetics showed no disturbance in the frequency of these antigens. Fifty-four of the juvenile onset type diabetics, with an average duration of disease of 3.2 years were tested for the presence of islet cell antibodies (ICAs). Thirty-two per cent were positive, the incidence decreasing from 70% in those patients tested within 1 year of diagnosis to zero in those patients tested within 1 year of diagnosis to zero in those patients tested more than 5 years after diagnosis. No correlation was found between the incidence of ICAs and either cell-mediated immune reactions or HLA type. B15 positive patients were associated with cell-mediated immune reactions to pancreatic antigens and with the presence of other tissue autoantibodies. HLA phenotypes were not associated with environmental data. Diabetic siblings had identical HLA A-B haplotypes more often than could be expected to occur by chance.