新型冠状病毒E蛋白B细胞表位的预测及鉴定OA北大核心CSTPCD

This work was aimed at predicting and verifying B-cell epitopes of SARS-CoV-2 E protein through bioinformatics methods,and clarifying the dominant B cell epitopes with mouse polyclonal antibody serum prepared through SARS-CoV-2 re-combinant E protein immunization and human positive serum vaccinated with inactivated SARS-CoV-2 vaccine.The structural and B-cell linear epitopes of SARS-CoV-2 E protein were predicted with SOPMA,Expasy,SWISS-MODEL,IEDB database,and Bepid-2.0 software.Candidate epitopes were expressed as GST-tagged recombinant protein fragments in an E.coli sys-tem,and their immunoreactivity with mouse and human poly-clonal positive serum against SARS-CoV-2 E protein was de-tected by western blotting and indirect ELISA,respectively.The epitope prediction results showed that E protein contained linear B cell epitopes Ser6-Val14 and Tyr57-Pro71,and the conformational epitopes of Glu8-Val12,Leu39-Tyr59,and Ser60-Leu65.The GST tagged recombinant E protein fragments of E1 and E3,containing Ser6-Val14 and Tyr57-Pro71 epitopes,respectively,as well as E2 without an epitope sequence as a control,were expressed in an E.coli expression system and successfully purified with an Ni-NTA column.Western blotting and indirect ELISA analysis indicated that all mouse and human SARS-CoV-2 positive sera positively reacted with only E1 and E3 proteins,but negatively reacted with E2 protein,thus indicating that the corresponding epitope prediction with Ser6-Val14 and Tyr57-Pro71 was correct.This study successfully predicted and preliminarily identified two linear B cell epitopes of SARS-CoV-2 E protein,thus providing a reference for the preparation of new coronavirus vaccines and the analysis of immune response characteristics.