Epitope mapping of severe acute respiratory syndrome-related coronavirus nucleocapsid protein with a rabbit monoclonal antibody

Xingui Tian; Chuncong Mo; Liling Zhou; Yujie Yang; Zhichao Zhou; Aiping You; Ye Fan; Wenkuan Liu; Xiao Li; Rong Zhou

doi:10.1016/j.virusres.2021.198445

Epitope mapping of severe acute respiratory syndrome-related coronavirus nucleocapsid protein with a rabbit monoclonal antibody

Virus Res. 2021 Jul 15:300:198445. doi: 10.1016/j.virusres.2021.198445. Epub 2021 May 5.

Authors

Xingui Tian¹, Chuncong Mo², Liling Zhou², Yujie Yang², Zhichao Zhou², Aiping You², Ye Fan², Wenkuan Liu², Xiao Li², Rong Zhou³

Affiliations

¹ State Key Laboratory of Respiratory Disease, National Clinical Research Center for Respiratory Disease, Guangzhou Institute of Respiratory Disease, the First Affiliated Hospital of Guangzhou Medical University, Guangzhou Medical University, Guangzhou 510182, China. Electronic address: tianxingui7902@163.com.
² State Key Laboratory of Respiratory Disease, National Clinical Research Center for Respiratory Disease, Guangzhou Institute of Respiratory Disease, the First Affiliated Hospital of Guangzhou Medical University, Guangzhou Medical University, Guangzhou 510182, China.
³ State Key Laboratory of Respiratory Disease, National Clinical Research Center for Respiratory Disease, Guangzhou Institute of Respiratory Disease, the First Affiliated Hospital of Guangzhou Medical University, Guangzhou Medical University, Guangzhou 510182, China. Electronic address: zhourong@gird.cn.

Abstract

The emergency SARS-CoV-2, a member of severe acute respiratory syndrome-related coronaviruses (SARSr-CoV), is still greatly harming the health of mankind. SARS-CoV-2-specific monoclonal antibodies (MAbs), which can identify SARS-CoV-2 from common human coronaviruses, are considered to extensively apply to developing rapid and reliable antigen assays. In this study we generated a rabbit MAb (RAb) detecting SARS-CoV-2 nucleocapsid protein (NP), which has cross-reaction with SARS-CoV-1 NP, but not with NPs of MERS and common human CoVs (OC43, NL63, 229E, and HKU1). With truncated NP fragments and synthesized peptides, the linear epitope detected by RAb was mapped in peptide N4-8, 393-407 amino acid residue (TLLPAADLDDFSKQL) of SARS-CoV-2 NP. This epitope N4-8 was highly conserved in SARSr-CoVs, including SARS-CoV-2, SARS-CoV-1, and bat CoV RaTG13 strain. However, the corresponding peptide of bat SARSr-CoV BtKY72 strain could not be recognized by RAb, which indicates amino acid D399 may be critical for N4-8 epitope detected by RAb. The present study will be conducive to developing reliable diagnosis for SARS-CoV-2 and gaining insights into the function of the SARS-CoV-2 N protein.

Keywords: Epitope; Monoclonal antibody; Nucleocapsid protein; SARS-CoV-2; SARSr-CoV.

Publication types

Research Support, Non-U.S. Gov't

MeSH terms

Antibodies, Monoclonal / immunology*
COVID-19 / diagnosis*
COVID-19 Serological Testing / methods*
Coronavirus Nucleocapsid Proteins / immunology*
Epitope Mapping
Humans
SARS-CoV-2* / immunology
SARS-CoV-2* / isolation & purification
Sensitivity and Specificity

Substances

Antibodies, Monoclonal
Coronavirus Nucleocapsid Proteins