Insulin, Pancreatic Polypeptide, and Glucagon Antibodies in Insulin-dependent Diabetes Mellitus

To assess the possible value of the use of high-purity pork insulin (HPPI) in the United States, the serum insulin (I), pancreatic polypeptide (PP), glucagon (G), and somatostatin (SRIF) antibody binding characteristics have been determined in 90 conventional insulin-treated diabetic subjects and related to their degree of metabolic control, as assessed by glycosylated hemoglobin (HbA₁) concentration. All diabetic subjects had antibodies to insulin, but there was no relationship between any of the antibody binding characteristics and HbA₁ level: 47% possessed PP antibodies; mean ± SEM HbA₁ in these patients was 14.5 ± 0.3%, identical to those without PP antibodies (14.5 ± 0.4%); 10% had G binding antibodies with HbA₁ levels of 14.6 ± 0.8%, similar to those without G antibodies. No subject possessed SRIF antibodies. This lack of correlation between antibody characteristics and metabolic control makes it unlikely that, in the majority of patients, treatment with a less immunogenic insulin (HPPI) versus conventional insulin will result in improved diabetic control.