Designing of a next generation multiepitope based vaccine (MEV) against SARS-COV-2: Immunoinformatics and in silico approaches

Tahir ul Qamar, Muhammad; Rehman, Abdur; Ashfaq, Usman Ali; Awan, Muhammad Qasim; Fatima, Israr; Shahid, Farah; Chen, Ling-Ling

Coronavirus disease 2019 (COVID-19) associated pneumonia caused by severe acute respiratory coronavirus 2 (SARS-COV-2) was first reported in Wuhan, China in December 2019. Till date, no vaccine or completely effective drug is available for the cure of COVID-19. Therefore, an effective vaccine against SARS-COV-2 is needed to be design. This study was conducted to design an effective multi-epitope vaccine (MEV) against SARS-COV-2. Seven antigenic proteins were taken as a target and epitopes (B cell, IFN-γ and T cell) were predicted. Highly antigenic and overlapping epitopes were shortlisted. Selected T cell epitopes indicated significant interactions with the HLA-binding alleles and 99.29% coverage of the world’s population. Finally, 505 amino acids long MEV was designed by connecting sixteen MHC class I and twelve MHC class II epitopes with suitable linkers and adjuvant. Linkers and adjuvant were added to enhance the immunogenicity response of the vaccine. The allergenicity, physiochemical properties, antigenicity and structural details of MEV were analyzed in order to ensure safety and immunogenicity. MEV construct was non-allergenic and antigenic. Molecular docking demonstrated a stable and strong binding affinity of MEV with TLR3 and TLR8. Codon optimization and in silico cloning ensured increased expression in the Escherichia coli K-12 system. However, to ensure its safety and immunogenic profile, the proposed vaccine needs to be experimentally validated.