Immunoinformatics study on SARS-CoV-۲ spike RBD for development a potent multi-epitope vaccine (MEV)

BACKGROUND AND OBJECTIVESHuman coronaviruses are well adapted to humans. However, new infectious viruses could evolve, such as ۲۰۱۹-nCoV. This novel virus was nominated as SARS-CoV-۲ by the ICTV. Its spike glycoprotein encompassing S۱ and S۲ subunits is the main determinant of virus neutralization. Among this, S۱ receptor-binding domain (RBD) becomes as an important target for the vaccine development. So, neutralizing antibodies (Nabs) and T-cell immune responses could be induced by its multiple epitopes [۱,۲,۳]. Accordingly, this study was aimed to predict the RBD B-Cell epitopes (BCEs) and their immunoinformatics properties for development a potent multi-epitope vaccine (MEV) in the next studies.MATERIALS AND METHODSThe spike Refseq (accession number: YP_۰۰۹۷۲۴۳۹۰.۱) was aligned by the NCBI database to determine the RBD. Then, the most potent linear/conformational BCEs were predicted using a multi- method approach via IEDB, ElliPro, Discotope, ABCpred, LBtope, and CBTope servers. The antigenicity, allergenicity, toxicity, and topology of these BCEs will also be investigated to highlight their importance [۴-۶].RESULTS AND DISCUSSIONIt was predicted that the spike glycoprotein contains many epitopes; however, the linear BCEs which predicted in the RBD were as follows: ۲ epitopes by the Bepipred Linear Epitope Prediction, ۲ highly antigenic epitopes by Kolaskar & Tongaonkar algorithm, ۲ epitopes by ElliPro, and ۴ epitopes showed surface accessibility by Emini Surface Accessibility. Moreover, ۲۲, ۱۰, and ۴ potential linear BCEs were predicted by LBtope, ABCpred, and CBTOPE, respectively. On the other hand, according to the Discotope and Ellipro, the ۳۲, and ۵۵ potential conformational epitopes located in the RBD, respectively. As it was shown multiple epitopes were located in the RBD which are overlapped together. More studies are doing to predict their probable roles to elicit immune responses.CONCLUSIONThe spike RBD mediates virus binding to the angiotensin-converting enzyme ۲ (ACE۲) receptor. Due to this critical role, it becomes a good candidate for therapeutics development. On the other hand, the in-silico approaches have gained much attention to rapid epitope prediction for the efficient vaccine design. Accordingly, many anti-SARS-CoV-۲ MEV have been developed. This highlights the practical importance of immunoinformatics studies [۱,۵,۷,۸]. In this regard, this work also provides new insights into BCEs of SARS-CoV-۲ which will improve and strength vaccine development after the comprehensive studies.

کلیدواژه ها:

SARS-CoV-۲ ، B-Cell epitopes ، Immunoinformatics ، Vaccine design ، RBD ، Multi-Epitope Vaccine