Cross-variant proof predictive vaccine design based on SARS-CoV-2 spike protein using immunoinformatics approach.

Background: Coronavirus Disease (COVID-19) is caused by the Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2). The SARS-CoV-2 virus is evolving continuously. The omicron variant of SARS-CoV-2 has the highest mutation in its spike protein, thus making the presently available vaccine ineffective or reducing its efficiency. Furthermore, the majority of the vaccines are constructed using a spike protein sequence from wild-type SARS-CoV-2. This raises the possibility of the virus evolving to the point where the vaccine's effectiveness is completely lost, even after booster doses. The study aims to develop a predictive vaccine as well as the epitopes for the updating of the vaccine sequences of currently available vaccines. In this study, following the immunoinformatics approach, predictive vaccine construction was done with the help of epitopes present on spike proteins of wild-type, delta, and omicron variants that encompass the majority of variants and possible new variants that arise from the combination of circulating variants. Results: The vaccine that was constructed was stable and immunogenic. The vaccine was constructed with the help of 18 B-cell epitopes, 5 MHC class I epitopes, and 6 MHC class II epitopes. The epitope conservancy analysis suggests that the vaccine will work for the previously known variant of concern. The vaccine bound to TLR4, TLR2, B-cell receptor chains A and B, and ACE2 receptors with a Conclusion: The study's findings indicate that the vaccine was both stable and immunogenic, providing a sufficient level of immunity. Following experimental validation, the vaccine can be used, and the epitopes can be employed for therapeutic purposes such as antibody synthesis. Graphical Abstract: Supplementary Information: The online version contains supplementary material available at 10.1186/s43088-023-00341-4.