The early detection of type 1 diabetes mellitus and latent autoimmune diabetes in adults (LADA) through rapid test reverse-flow immunochromatography for glutamic acid decarboxylase 65 kDa (GAD65)

Aulanni'am Aulanni'am; Dyah Kinasih Wuragil; Hendra Susanto; Anita Herawati; Yulianto Muji Nugroho; Wahyu Nur Laili Fajri; Perdana Finawati Putri; Susiati Susiati; Jerry Dwi Trijoyo Purnomo; Ahmad Taufiq; Djoko Wahono Soeatmadji

doi:10.1016/j.heliyon.2021.e08695

The early detection of type 1 diabetes mellitus and latent autoimmune diabetes in adults (LADA) through rapid test reverse-flow immunochromatography for glutamic acid decarboxylase 65 kDa (GAD₆₅)

Heliyon. 2021 Dec 31;8(1):e08695. doi: 10.1016/j.heliyon.2021.e08695. eCollection 2022 Jan.

Affiliations

¹ Faculty of Sciences, Brawijaya University, Indonesia.
² Faculty of Veterinary Medicine, Brawijaya University, Indonesia.
³ Biosains Institute, Brawijaya University, Indonesia.
⁴ Faculty of Mathematics and Natural Sciences, Universitas Negeri Malang, Indonesia.
⁵ Faculty of Science and Data Analytics, Institut Teknologi Sepuluh November, Indonesia.
⁶ Faculty of Medicine, Brawijaya University, Indonesia.

Abstract

Background: Diabetes mellitus (DM) is a chronic and costly disease that has become a primary concern worldwide. Type 1 diabetes mellitus is categorized as an autoimmune disease, which results in islet cell apoptosis and insulin-dependent. GAD₆₅ is known as a potential marker of impaired pancreatic β cell function that appears in the initial phase of type 1 DM and latent autoimmune diabetes in adults (LADA). This study aimed to develop a novel rapid test of anti-GAD₆₅ autoantibodies in human serum samples.

Methods: We have developed a rapid test for anti-GAD65 autoantibodies in this assay based on the reverse-flow immunochromatography method. Human recombinant-protein antigen for GAD₆₅ was attached as the control line over the nitrocellulose membrane. On the other side, the goat anti-mouse immunoglobulin G (IgG) was coated on the same membrane as a control line. The positive result for GAD₆₅ was confirmed by a colloidal gold signal on the strip. Our novel assay analyzed 276 healthy subjects and 51 type 1 diabetes individuals serum samples from several ethnicities in Indonesia for this study.

Results: Among the 276 healthy samples, 225 samples were identified as positive for anti-GAD₆₅ autoantibodies, while 51 samples were negative. Interestingly, the positive results for anti-GAD₆₅ autoantibodies were linear to the decreasing of high-density lipoprotein (HDL) levels and inversely associated with triglyceride levels. A significant correlation with age was observed in all groups. The sensitivity and specificity test proved that this kit has higher accuracy (AUC value = 0.960).

Conclusion: The significant advantages of our rapid test for anti-GAD₆₅ autoantibodies provide higher sensitivity, specificity, and stability compared to previous commercial kits. Therefore, it could be proposed as the future clinical diagnostic kit for patient management of type 1 DM.

Keywords: Autoimmune; Glutamic acid decarboxylase 65 (GAD65); Rapid test; Type 1 diabetes mellitus.