An in silico approach to design a novel multi-epitope peptide vaccine against Helicobacter Pylori

Introduction & Objectives: Helicobacter pylori, the most common human infectious agent, is a gram-negative bacterium that colonizes in the stomach and causes gastritis, peptic ulcers, adenocarcinoma, and MALT (mucosa-associated lymphoid tissue) lymphoma. This bacterium which has recognized as carcinogen by the World Health Organization (WHO), has infected 50% of the world population on average. Although because of its high prevalence rate and antibiotics resistance, development of a vaccine has been accepted as an efficient strategy in prevention of mentioned cancers, it has remained as a challenge so far and today immunoinformatics is a promising way that helps to solve this problem.Methods: In this study, three H. Pylori antigens, including UreB, HpaA, and NapA were selected which have an important role in its pathogenicity or colonization. Since the T CD4⁺ cells are the most important of the immune system cells against H. Pylori, so their potential immunodominant T CD4⁺ epitopes were selected by four relevant servers including IEDB, MHC2Pred, MHCPred, and RANKPEP and after evaluation by IFNepitope server, were joined to each other by KK and GPGPG linkers. As adjuvant, flagellin D0 and D1 domains were added to each side of the construct by a flexible linker, EAAAK, to increase its immunity. Then the designed vaccine was evaluated in multiple aspects.Results: The final construct was estimated as antigenic (0.93) and nonallergenic with appropriate solubility (0.63), molecular weight (64581.40), isoelectric pH (9.37), and instability index (29.32).Conclusion: Based on the current study, this vaccine can serve as a promising anti-H. Pylori vaccine and gastric cancer-preventive candidate.

کلیدواژه ها:

Helicobacter Pylori ، Vaccine ، UreB ، Gastric cancer ، Immunoinformatics ، Design