Background: The most important point about the pathogenesis of idiopathic autoimmune diabetes is related to the presence of major autoantigens. One of these important autoantigens that has been identified as targets of humoral autoimmunity in type 1 diabetes is insulin. Insulin autoantibodies are often the first autoantibodies to be detected in individuals with type 1 diabetes. The identification of unique insulin epitopes that can be recognized by T cells could help in the development of vaccines aimed at preventing the destruction of pancreatic beta cells in diabetes.
Methods: The objective of the present investigation was to ascertain the most effective epitopes for the designing of a vaccine aimed at insulin, a significant autoantigen associated with type 1 diabetes mellitus. The UniProt database provided the amino acid sequence of insulin, which was used for epitope identification from the IEDB server. In the process of epitope identification, we employed the prevalent human alleles DRB1*01:01, DRB3*01:01, DRB4*01:01, and DRB5*01:01, each of which comprises a length of 15 base pairs.
Findings: A common insulin epitope was identified using two IEDB servers: the IEDB MHC-II binding prediction tool (http://tools.iedb.org/mhcii/) and TEPITOOL (http://tools.iedb.org/tepitool/). The consensus epitope sequence was ERGFFYTPKTRREAE.
Conclusion: Since the development of vaccine design for high-prevalence diseases such as diabetes holds promise for the treatment and prevention of these diseases, in this study we decided to identify common epitopes associated with insulin, which is a key component in vaccine design.