A Novel Multi-epitope Vaccine Against SARS-CoV-2 Variants of Concern Strains Applying Immunoinformatics Approaches

Background: The newly emerged coronavirus, SARS-CoV-2, the causative agent of the COVID-19 disease, appeared in Wuhan, China in December 2019 and led to the death of millions of people. The pandemic has increased the demand for effective vaccines and treatments worldwide. Due to the changes in the virus genome caused by mutation, variants with higher transmission ability and pathogenicity have emerged and raised excessive concerns about the efficiency of the developed vaccines. This study aimed to design a multi-epitope vaccine that targets the primary SARS-CoV-2 strain and its five variants of concern using immunoinformatics approaches. Methods: B-cell, cytotoxic T lymphocytes (CTLs) and helper T lymphocytes epitopes of the conserved and mutated SARS-CoV-2 surface glycoproteins were predicted using immunoinformatics approaches. These epitopes were attached utilizing appropriate linkers, and to provoke the immune response efficiently, the cholera toxin B subunit was added as an adjuvant. Results: Analyses by different bioinformatics softwares revealed that the designed vaccine’s high safety, stability, and efficacy. Conclusion: In this study, the vaccine designed by immunoinformatics tools showed specific reactivity to Toll-like receptor 4. Given the validation of other epitope-based vaccines, our vaccine might be capable of providing strong immunity in a wide range of populations.