Designing a Novel Multi-epitope Peptide Vaccine Against Pathogenic Shigella spp. Based Immunoinformatics Approaches

Shigella spp. causes severe diarrhea and dysenteric disease, which known as shigellosis. Until now, no licensed vaccine is available for shigellosis; therefore, development of a novel strategy to produce an effective vaccine is urgently needed. Shigella invasion plasmid antigens (Ipas) such as, Ipa B and Ipa D are conserved, cross-reactive and highly immunogenic antigens among Shigella spp. Outer membrane protein (Omp) A family of Shigella spp. incites effective immune; therefore, Ipa B, Ipa D and Omp A are superb candidate antigens for designing a cross-protective vaccine against Shigella . In this study, different immunoinformatics approaches were used to design a novel multi-epitope peptide vaccine against Shigella spp. CD4 + T cell immune response has an essential role in eradication of shigellosis; in this regard, Ipa B, Ipa D and Omp A were analyzed to identify Helper T cell lymphocytes (HTL) epitopes by various immunoinformatics servers. D0 and D1 flagellin domains of salmonella enteric were used as Toll like receptor 5 (TLR5) agonist which plays a role as mucosal adjuvant. All mentioned segments were fused together by proper amino acid linkers. Linear and conformational B cell epitopes were also determined in vaccine construct. Totally, we believe that the designed vaccine candidate is able to induce cellular and humoral as well as mucosal secretory IgA (sIgA) immunity against shigellosis.