Antibody formation and insulin requirements in diabetic children during treatment with purified commercial pork insulins.

40 diabetic children (20 female, 20 male, mean age 8.5 ys, ranging from 0.8 to 14.3 ys), were treated with either of two purified porcine insulin preparations, Komb-Insulin CS (Hoechst) "CS": n = 21, and Semilente MC (Novo) "MC": n = 19, the latter being further purified by ion exchange chromatography. Circulating IgG-antibodies formed in 39 out of 40 subjects during the observation period of more than 2 years. Insulin binding-capacities below 2 mU/ml (mean value after 12 months: 0.45 mU/ml) were found following MC and considerably higher concentrations (mean value after 12 months: 5.16 mU/ml) following CS administration. However, only 52% of the CS-group (n = 11) showed high individual responses (subgroup II), many of which exceeded 5 mU/ml, while the other half (subgroup I) exhibited values as low as those in the MC-subjects. The ratio of girls to boys was high (8 vs 3) in subgroup II, and low (2 vs 8) in subgroup I. Despite great differences in antibody formation, no differences in insulin requirements were noted between the MC- and the CS-groups. Within the CS-group, however, some positive relationship between these parameters was found 6 months and 12 months after the start of therapy, but this did not necessarily apply to individual subjects. Short-term (metabolic control) and long-term effects of therapy (growth) were not different in the MC- and CS-subjects. From these results it may be concluded that antibody formation does not affect insulin requirements or metabolic control during relatively short-term treatment. Provided that antibodies have no direct relation to future vascular changes, both insulin preparations used in this study are equally well-situated for long-term treatment in children and adolescents.