• Identification of common epitope for GAD65 in three different servers
  • Masumeh Jalalvand,1 Hamed Esmaeil Lashgarian,2 leila Abkhooie,3 sedighe momenzade,4 Amirmasoud Jalalvand,5 Hadis Rahimi,6,*
    1. Assistant Professor, Department of Medical Biotechnology, Faculty of Medicine, Lorestan University of Medical Sciences, Khorramabad, Iran
    2. Associate Professor, Department of Medical Genetics and Biotechnology, Faculty of Medicine, Lorestan University of Medical Sciences, Khorramabad, Iran.
    3. Assistant Professor, Department of Medical Biotechnology, Faculty of Medicine, Lorestan University of Medical Sciences, Khorramabad, Iran
    4. Assistant Professor of Medical Biotechnology ,School of Paramedicine, Bushehr University of Medical Sciences, Bushehr, Iran.
    5. Department of Medical Biotechnology, Faculty of Medicine, Lorestan University of Medical Sciences, Khorramabad, Iran
    6. Department of Clinical Biochemistry, Faculty of Medicine, Lorestan University of Medical Sciences, Khorramabad, Iran.


  • Introduction: Introduction: The incidence of diabetes mellitus (DM) has experienced a fourfold increase over a period of three decades, specifically from 1980 to 2014, affecting in excess of 400 million individuals globally [1]. Type 1 diabetes mellitus (T1DM) accounts for approximately 5% of the total DM cases and is attributed to the autoimmune-mediated destruction of pancreatic β-cells (1-3). Several antigens have been identified as targets of humoral autoimmunity in type 1 diabetes, one of which is the 65-kDa isoform of glutamic acid decarboxylase (GAD65) (4, 5). Therefore, identifying unique epitopes on GAD65 that are recognized by T cells may aid in the development and design of vaccines aimed at preventing pancreatic beta cell destruction in diabetes.
  • Methods: Methods: The aim of this study is to identify the best epitopes for designing a vaccine targeting the glutamic acid decarboxylase (GAD) protein, a key autoantigen associated with type 1 diabetes. This content reads as if it is human-written. The UniProt database provided the GAD65 amino acid sequence, which was then used to identify MHC Class II epitopes using the IEDB server. We used the common human alleles DRB104:01 and DRB103:01, which have a length of 15, in the epitope identification process.
  • Results: Results: We were able to find a common epitope for GAD65 by the three IEDB servers at http://tools.iedb.org/mhcii/, TEPITOOL at http://tools.iedb.org/tepitool/, and syfpeithi at https://www.syfpeithi.de/bin/MHCServer.dll/EpitopePrediction.htm. The sequence of this common epitope for GAD65 in these three servers was VNFFRMVISNPAATH.
  • Conclusion: Conclusion: The development of diabetes vaccine designs targeting GAD65 holds promise for the treatment and prevention of diabetes. The identification of common epitopes associated with GAD65 constitutes a critical component in the design of effective anti-diabetic vaccines. Consequently, given the characteristics of humoral autoimmunity, GAD65 in type 1 diabetes (T1D) is a target for investigation and development of more precise vaccine design and therapeutic approaches. 1. Control CfD, Prevention. Estimates of diabetes and its burden in the United States: National diabetes statistics report. Atlanta: Centers for Disease Control and Prevention. 2014. 2. Roglic G. WHO Global report on diabetes: A summary. International Journal of Noncommunicable Diseases. 2016;1(1):3-8. 3. Keshavarzi E, Noveiry BB, Rezaei N. The relationship between GAD65 autoantibody and the risk of T1DM onset. Journal of Diabetes & Metabolic Disorders. 2022;21(2):1935-42. 4. Baekkeskov S, Nielsen JH, Marner B, Bilde T, Ludvigsson J, Lernmark A. Autoantibodies in newly diagnosed diabetic children immunoprecipitate human pancreatic islet cell proteins. Nature. 1982;298(5870):167-9. 5. Baekkeskov S, Aanstoot H-J, Christgai S, Reetz A, Solimena M, Cascalho M, et al. Identification of the 64K autoantigen in insulin-dependent diabetes as the GABA-synthesizing enzyme glutamic acid decarboxylase. Nature. 1990;347(6289):151-6.
  • Keywords: Keyword: Common epitope, Type 1 diabetes mellitus, GAD65