Design and Recombinant Expression of a multiepitope Vaccine Candidate Against Pathogenic Species of Shigella

Shigellosis is a form of acute intestinal infection and one of the global health problems that occur in human by pathogenic species of Shigella. Producing a cost-effective and protective vaccine against the pathogenic strains of these bacteria will have a significant effect on the improvement of public health. The purpose of this research was to design, express and purify a multiepitope protein as a candidate vaccine against Shigella pathogenic species.

The multi-epitope protein-encoding Ipas, Omps and IcsA genes was designed based on previous bioinformatics assessments and synthesized in pET28a (+) expression vector. Since no detectable expression was observed, the gene was subcloned into pET32a (+). The pET32a (+) recombinant vector containing the desired gene was transferred into Escherichia coli BL21 (DE3) and the expression of the recombinant protein was induced using IPTG. The protein was purified using a nickel column. Finally, the Western blotting method was used to confirm the expression of the recombinant protein.

The sub-cloning of the gene was confirmed using PCR reaction. Gene expression analysis showed that the desired protein had a suitable expression. Western blotting analysis confirmed the expression of the recombinant protein.

The expressed and purified multi-epitope recombinant protein, containing the main epitopes of the common antigens of pathogenic Shigella species could be achieved as the first step to design a multiepitope vaccine candidate against shigellosis.