{"title":"Development of in vitro plaque-based assay for assessment of antibody-dependent enhancement in SARS-CoV-2 infection","authors":"Pimploy Rattanaamnuaychai , Surachet Benjathummarak , Pannamthip Pitaksajjakul , Pongrama Ramasoota , Yong Poovorawan , Hiroto Mizushima , Masashi Tatsumi , Yoshiharu Matsuura , Atsushi Yamanaka","doi":"10.1016/j.jim.2025.113919","DOIUrl":null,"url":null,"abstract":"<div><div>Antibody-dependent enhancement (ADE) of infection is a concerning phenomenon in SARS-CoV-2 infection, since it may develop disease severity. Although ADE has been demonstrated in animal models, the pathogenic mechanism has not been fully elucidated. The present study aimed to develop a simple assay system for detecting SARS-CoV-2 ADE activity in any antibody specimen. Vero E6/TMPRSS2/FcγRIIA, a Vero E6 cell strain expressing TMPRSS2 and FcγRIIA, was established. Seventeen plasma samples from convalescent patients and seven commercial antibodies were used as antibody specimens. Vero E6/TMPRSS2/FcγRIIA cells, infected with SARS-CoV-2 in the presence of antibody, were shown to exhibit ADE activity, with the plaque number increasing dramatically compared with the control in the absence of antibody specimens. Most plasmas displayed both ADE and neutralizing activities. Furthermore, 6 commercial antibodies recognizing structural proteins (membrane, nucleocapsid, envelope, and spike [transmembrane and cytoplasmic domains] proteins and non-structural protein ORF7) showed no potential ADE activity, while a commercial antibody recognizing spike RBD displayed ADE activity. These results indicate that antibodies possessing neutralizing and/or enhancing activity might be generated by either viral infection or vaccination. The present ADE assay may help to evaluate the risk of disease severity for individuals upon future reinfection, vaccination and/or immunotherapy.</div></div>","PeriodicalId":16000,"journal":{"name":"Journal of immunological methods","volume":"543 ","pages":"Article 113919"},"PeriodicalIF":1.6000,"publicationDate":"2025-08-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":"0","resultStr":null,"platform":"Semanticscholar","paperid":null,"PeriodicalName":"Journal of immunological methods","FirstCategoryId":"3","ListUrlMain":"https://www.sciencedirect.com/science/article/pii/S002217592500119X","RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":null,"EPubDate":"","PubModel":"","JCR":"Q4","JCRName":"BIOCHEMICAL RESEARCH METHODS","Score":null,"Total":0}
引用次数: 0
Abstract
Antibody-dependent enhancement (ADE) of infection is a concerning phenomenon in SARS-CoV-2 infection, since it may develop disease severity. Although ADE has been demonstrated in animal models, the pathogenic mechanism has not been fully elucidated. The present study aimed to develop a simple assay system for detecting SARS-CoV-2 ADE activity in any antibody specimen. Vero E6/TMPRSS2/FcγRIIA, a Vero E6 cell strain expressing TMPRSS2 and FcγRIIA, was established. Seventeen plasma samples from convalescent patients and seven commercial antibodies were used as antibody specimens. Vero E6/TMPRSS2/FcγRIIA cells, infected with SARS-CoV-2 in the presence of antibody, were shown to exhibit ADE activity, with the plaque number increasing dramatically compared with the control in the absence of antibody specimens. Most plasmas displayed both ADE and neutralizing activities. Furthermore, 6 commercial antibodies recognizing structural proteins (membrane, nucleocapsid, envelope, and spike [transmembrane and cytoplasmic domains] proteins and non-structural protein ORF7) showed no potential ADE activity, while a commercial antibody recognizing spike RBD displayed ADE activity. These results indicate that antibodies possessing neutralizing and/or enhancing activity might be generated by either viral infection or vaccination. The present ADE assay may help to evaluate the risk of disease severity for individuals upon future reinfection, vaccination and/or immunotherapy.
期刊介绍:
The Journal of Immunological Methods is devoted to covering techniques for: (1) Quantitating and detecting antibodies and/or antigens. (2) Purifying immunoglobulins, lymphokines and other molecules of the immune system. (3) Isolating antigens and other substances important in immunological processes. (4) Labelling antigens and antibodies. (5) Localizing antigens and/or antibodies in tissues and cells. (6) Detecting, and fractionating immunocompetent cells. (7) Assaying for cellular immunity. (8) Documenting cell-cell interactions. (9) Initiating immunity and unresponsiveness. (10) Transplanting tissues. (11) Studying items closely related to immunity such as complement, reticuloendothelial system and others. (12) Molecular techniques for studying immune cells and their receptors. (13) Imaging of the immune system. (14) Methods for production or their fragments in eukaryotic and prokaryotic cells.
In addition the journal will publish articles on novel methods for analysing the organization, structure and expression of genes for immunologically important molecules such as immunoglobulins, T cell receptors and accessory molecules involved in antigen recognition, processing and presentation. Submitted full length manuscripts should describe new methods of broad applicability to immunology and not simply the application of an established method to a particular substance - although papers describing such applications may be considered for publication as a short Technical Note. Review articles will also be published by the Journal of Immunological Methods. In general these manuscripts are by solicitation however anyone interested in submitting a review can contact the Reviews Editor and provide an outline of the proposed review.