T-cell epitope-based subunit vaccine design in case of SARS-CoV-2 infection

Seema Mishra
Department of Biochemistry
School of Life Sciences, University of Hyderabad-500046 India

Urgent attention is required to tackle SARS-CoV-2, the causative virus for Covid19, which has created a pandemic. Peptide-based subunit vaccines are considered relatively safer alternative to mRNA or inactivated viral vaccines for an elderly population which are the prime targets. Powerful Immunoinformatics tools have made it plausible to design new vaccine candidates for T cell epitope-based multi-subunit vaccines (1). Utilizing higher HLA-I and HLA-II binding capacities, proteasomal cleavage and TAP transporter-binding efficiency, a candidate epitope set has been enlisted, spread over the SARS-CoV-2 proteome. A high level of promiscuity and immunogenicity were the other criteria being applied and clustering of the cytotoxic T lymphocyte (CTL) and helper T lymphocyte (HTL) epitopes provided a further narrowed-down set. Interestingly, a few candidate epitopes in this list were identical in sequence to previous SARS-CoV characterized epitopes, the latter epitopes were found to be recognized in humans and transgenic mouse. Consequently, a ranked list of epitopes was obtained that in addition to being considered as likely candidates, also provided crucial insights into SARS-CoV-2 immunopathological mechanisms (2). This talk will focus on such studies done with a view to design and further utilize these candidate epitopes into a likely effective multi-epitope subunit vaccine after due in vitro MHC-peptide binding, T cell stimulation and in vivo assays.

1. Mishra S, Sinha S. 2006 Prediction and molecular modeling of T cell epitopes derived from placental alkaline phosphatase for use in cancer immunotherapy. J. Biomol. Struct. Dyn. 24, 109–121. (doi:10.1080/07391102.2006. 10507104).

2.  Mishra S. 2020 Designing of cytotoxic and helper T cell epitope map provides insights into the highly contagious nature of the pandemic novel coronavirus SARS-CoV-2. R. Soc. Open Sci. 7 : 201141 ( http://dx.doi.org/10.1098/rsos.201141).