Assessment of Anti-Zinc Transporter Protein-8 Function in Adults with Type 1 Diabetes

Background: Anti-glutamic acid decarboxylase antibodies (GAD65A), anti-tyrosine phosphatase antibodies (IA-2), insulinoma-associated 2 autoantibodies (IA-2A), and anti-zinc transporter antibodies (Zn-T8A) are some of the most important blood tests used to diagnose type 1 diabetes mellitus (T1DM). Integrating zinc transporter 8 autoantibody (ZnT8A) into the conventional diagnostic protocol for T1DM may enhance the overall sensitivity of autoantibody detection and may predict early complications. Objectives: To analyze the presence of type 1 diabetes-related autoantibodies (GAD65A, IA-2A, and ZnT8A) and to determine any link with age, gender, and duration of the illness in adult populations. Methods: This case-control research was performed at four teaching hospitals in Basra city during a five-month period on 100 adult patients confirmed to have T1DM and on 50 apparently healthy controls. Serum concentrations of ZnT8A, GAD65A, and IA-2A were individually assessed utilizing ELISA in both cases and control groups. Results: A statistically significant difference exists in the concentrations of ZnT8A, GAD65A, and IA-2A autoantibodies between the case and control groups. All three immunological markers had no correlation with sex and duration of disease. ZnT8A positivity was associated with an earlier age of onset (OR=2.50, p=0.039) and the presence of IA-2A (OR=2.65, p=0.015). No correlation was found between ZnT8A and GAD65A. Conclusions: ZnT8A shows the highest concentration among the three studied autoantibodies in both the acute-onset and slowly progressive T1DM patient groups and is considered an important serological marker of T1DM with other immunological markers for this disease.