Structure and biological functions of human IgD. V. Insulin antibodies of the IgD class in sera from some diabetic patients.

Insulin antibodies were detected in the sera of diabetics who had received injections of animal insulin. The incidence of anti-insulin antibodies varied from 47 to 97% depending upon whether individual diabetic serum samples were compared with the highest 'normal' serum binding value or the mean binding value of all 'normal' nondiabetic sera. Approximately 64 of our diabetic patients had detectable IgD anti-insulin antibodies but only approximately 14% of the patients had values clearly above those found in 'normal' nondiabetic sera.