Insulin antibody response to bovine insulin therapy: functional significance among insulin requiring young diabetics in India

The majority of young diabetics in India prefer to use low-cost bovine insu lin for economic reasons. Therefore, the question of insulin antibody respo nse to bovine insulin and its functional significance is still relevant in the Indian context. We assessed insulin antibody response in 52 young diabe tics (type 1, n = 25, malnutrition modulated form of diabetes, n = 19 and f ibrocalculous pancreatopathy (FCP) n = 8) on bovine insulin therapy (mean d uration 3.0 +/- 2.1 years) using an internationally standardised in-house r adioligand assay. The functional significance of insulin antibody was asses sed by calculating their affinity constant, maximum binding capacity and to tal insulin binding power by Scatchard analysis (type 1, n=14, malnutrition modulated form of diabetes, n= 11). All the patients treated with bovine i nsulin showed high titers of insulin antibodies with S.D. score ranging fro m 5.1 to 42.0. No significant difference was observed in the mean S.D. scor e of insulin antibodies in the three diabetic groups. The mean daily insuli n dose, maximum insulin binding capacity and total insulin binding power we re significantly higher in type 1 when compared to the malnutrition modulat ed form of diabetes (36 +/- 8 vs. 26 +/- 11 IU/day, P < 0.05; 9.7 +/- 7.8 v s. 4.0 +/- 3.9 nmol/l, P = 0.03 and 59 +/- 29 vs. 29 +/- 43, P = 0.01, resp ectively). Insulin antibodies S.D. score and its affinity did not show sign ificant relationship with daily insulin dose and glycemic control (HbAl) at admission. Only 24 +/- 7% variations in daily insulin requirement were acc ounted for by total insulin binding power. There was a significant inverse relationship between insulin antibody S.D. score and duration of insulin th erapy (r = - 0.4172, P < 0.0004). To conclude, insulin antibody response fo llowing bovine insulin therapy is not different among type 1, malnutrition modulated form of diabetes and FCP diabetes. The insulin antibody response to bovine insulin therapy does not contribute significantly to increase in daily insulin requirement in bovine insulin treated insulin requiring young diabetics. (C) 2000 Elsevier Science Ireland Ltd. All rights reserved.