The instantly blocking-based fluorescent immunochromatographic assay for the detection of SARS-CoV-2 neutralizing antibody

Yizhe Li; Jinyong He; Ying Zhang; Dan Liang; Jiaqi Zhang; Ruili Ji; Yue Wu; Zejie Su; Changwen Ke; Ning Xu; Yong Tang; Jianhua Xu

doi:10.3389/fcimb.2023.1203625

The instantly blocking-based fluorescent immunochromatographic assay for the detection of SARS-CoV-2 neutralizing antibody

Front Cell Infect Microbiol. 2023 Sep 5:13:1203625. doi: 10.3389/fcimb.2023.1203625. eCollection 2023.

Authors

Yizhe Li¹, Jinyong He¹, Ying Zhang², Dan Liang³, Jiaqi Zhang¹, Ruili Ji¹, Yue Wu¹, Zejie Su¹, Changwen Ke³, Ning Xu⁴, Yong Tang², Jianhua Xu⁵

Affiliations

¹ Department of Laboratory Medicine, Shunde Hospital of Guangzhou University of Chinese Medicine, Foshan, Guangdong, China.
² Department of Bioengineering, Guangdong Province Engineering Research Center of Antibody Drug and Immunoassay, Jinan University, Guangzhou, Guangdong, China.
³ Guangdong Provincial Institute of Public Health, Guangdong Center for Disease Control and Prevention, Guangzhou, Guangdong, China.
⁴ Department of Laboratory Science, The Second Affiliated Hospital of Guangzhou University of Chinese Medicine, Guangzhou, Guangdong, China.
⁵ Maoming Hospital of Guangzhou University of Chinese Medicine, Maoming, Guangdong, China.

Abstract

Introduction: At present, there is an urgent need for the rapid and accurate detection of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) neutralizing antibodies (NAbs) to evaluate the ability of the human body to resist coronavirus disease 2019 (COVID-19) after infection or vaccination. The current gold standard for neutralizing antibody detection is the conventional virus neutralization test (cVNT), which requires live pathogens and biosafety level-3 (BSL-3) laboratories, making it difficult for this method to meet the requirements of large-scale routine detection. Therefore, this study established a time-resolved fluorescence-blocking lateral flow immunochromatographic assay (TRF-BLFIA) that enables accurate, rapid quantification of NAbs in subjects.

Methods: This assay utilizes the characteristic that SARS-CoV-2 neutralizing antibody can specifically block the binding of the receptor-binding domain (RBD) of the SARS-CoV-2 spike protein and angiotensin-converting enzyme 2 (ACE2) to rapidly detect the content of neutralizing antibody in COVID-19-infected patients and vaccine recipients.

Results: When 356 samples of vaccine recipients were measured, the coincidence rate between this method and cVNT was 88.76%, which was higher than the coincidence rate of 76.97% between cVNT and a conventional chemiluminescence immunoassay detecting overall binding anti-Spike-IgG. More importantly, this assay does not need to be carried out in BSL-2 or 3 laboratories.

Discussion: Therefore, this product can detect NAbs in COVID-19 patients and provide a reference for the prognosis and outcome of patients. Simultaneously, it can also be applied to large-scale detection to better meet the needs of neutralizing antibody detection after vaccination, making it an effective tool to evaluate the immunoprotective effect of COVID-19 vaccines.

Keywords: COVID-19 vaccine; conventional virus neutralization test; fluorescent lateral flow immunochromatographic assay; neutralizing antibody; receptor binding domain.

Publication types

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

MeSH terms

Antibodies, Neutralizing
Antibodies, Viral
COVID-19 Vaccines
COVID-19* / diagnosis
Humans
Immunoassay
SARS-CoV-2*

Substances

spike protein, SARS-CoV-2
COVID-19 Vaccines
Antibodies, Viral
Antibodies, Neutralizing

Grants and funding

This work was supported by the Basic and Applied Basic Research Foundation of Guangdong Province (2021A1515010174), the Fundamental Research Funds for the Central Universities (21620108), the Guangzhou Civil Affairs Bureau Planned Project of Science and Technology (2021MZK22), and the Emergency Key Program of Guangzhou Laboratory (EKPG21-27).