tetano
Editor, Senior Moderator
J Clin Microbiol
. 2022 May 16;e0007522.
doi: 10.1128/jcm.00075-22. Online ahead of print.
Fcγ-Receptor-Based Enzyme-Linked Immunosorbent Assays for Sensitive, Specific, and Persistent Detection of Anti-SARS-CoV-2 Nucleocapsid Protein IgG Antibodies in Human Sera
Christina Deschermeier[SUP] 1 [/SUP], Christa Ehmen[SUP] 1 [/SUP], Ronald von Possel[SUP] 2 3 [/SUP], Carolin Murawski[SUP] 1 [/SUP], Ben Rushton[SUP] 1 [/SUP], John Amuasi[SUP] 4 [/SUP], Nimako Sarpong[SUP] 5 [/SUP], Oumou Maiga-Ascofaré[SUP] 5 6 [/SUP], Raphael Rakotozandrindrainy[SUP] 7 [/SUP], Danny Asogun[SUP] 8 [/SUP], Yemisi Ighodalo[SUP] 8 [/SUP], Lisa Oestereich[SUP] 2 6 [/SUP], Sophie Duraffour[SUP] 2 6 [/SUP], Meike Pahlmann[SUP] 2 6 [/SUP], Petra Emmerich[SUP] 2 3 [/SUP]
Affiliations
Abstract
Sensitive and specific serological tests are mandatory for epidemiological studies evaluating severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) prevalence as well as coronavirus disease 2019 (COVID-19) morbidity and mortality rates. The accuracy of results is challenged by antibody waning after convalescence and by cross-reactivity induced by previous infections with other pathogens. By employing a patented platform technology based on capturing antigen-antibody complexes with a solid-phase-bound Fcγ receptor (FcγR) and truncated nucleocapsid protein as the antigen, two SARS-CoV-2 IgG enzyme-linked immunosorbent assays (ELISAs), featuring different serum and antigen dilutions, were developed. Validation was performed using a serum panel comprising 213 longitudinal samples from 35 COVID-19 patients and a negative-control panel consisting of 790 pre-COVID-19 samples from different regions of the world. While both assays show similar diagnostic sensitivities in the early convalescent phase, ELISA 2 (featuring a higher serum concentration) enables SARS-CoV-2 IgG antibody detection for a significantly longer time postinfection (≥15 months). Correspondingly, analytical sensitivity referenced to indirect immunofluorescence testing (IIFT) is significantly higher for ELISA 2 in samples with a titer of ≤1:640; for high-titer samples, a prozone effect is observed for ELISA 2. The specificities of both ELISAs were excellent not only for pre-COVID-19 serum samples from Europe, Asia, and South America but also for several challenging African sample panels. The SARS-CoV-2 IgG FcγR ELISAs, methodically combining antigen-antibody binding in solution and isotype-specific detection of immune complexes, are valuable tools for seroprevalence studies requiring the (long-term) detection of anti-SARS-CoV-2 IgG antibodies in populations with a challenging immunological background and/or in which spike-protein-based vaccine programs have been rolled out.
Keywords: immunoassay; immunoglobulins; infectious disease; laboratory methods and tools; viral diseases.
. 2022 May 16;e0007522.
doi: 10.1128/jcm.00075-22. Online ahead of print.
Fcγ-Receptor-Based Enzyme-Linked Immunosorbent Assays for Sensitive, Specific, and Persistent Detection of Anti-SARS-CoV-2 Nucleocapsid Protein IgG Antibodies in Human Sera
Christina Deschermeier[SUP] 1 [/SUP], Christa Ehmen[SUP] 1 [/SUP], Ronald von Possel[SUP] 2 3 [/SUP], Carolin Murawski[SUP] 1 [/SUP], Ben Rushton[SUP] 1 [/SUP], John Amuasi[SUP] 4 [/SUP], Nimako Sarpong[SUP] 5 [/SUP], Oumou Maiga-Ascofaré[SUP] 5 6 [/SUP], Raphael Rakotozandrindrainy[SUP] 7 [/SUP], Danny Asogun[SUP] 8 [/SUP], Yemisi Ighodalo[SUP] 8 [/SUP], Lisa Oestereich[SUP] 2 6 [/SUP], Sophie Duraffour[SUP] 2 6 [/SUP], Meike Pahlmann[SUP] 2 6 [/SUP], Petra Emmerich[SUP] 2 3 [/SUP]
Affiliations
- PMID: 35574677
- DOI: 10.1128/jcm.00075-22
Abstract
Sensitive and specific serological tests are mandatory for epidemiological studies evaluating severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) prevalence as well as coronavirus disease 2019 (COVID-19) morbidity and mortality rates. The accuracy of results is challenged by antibody waning after convalescence and by cross-reactivity induced by previous infections with other pathogens. By employing a patented platform technology based on capturing antigen-antibody complexes with a solid-phase-bound Fcγ receptor (FcγR) and truncated nucleocapsid protein as the antigen, two SARS-CoV-2 IgG enzyme-linked immunosorbent assays (ELISAs), featuring different serum and antigen dilutions, were developed. Validation was performed using a serum panel comprising 213 longitudinal samples from 35 COVID-19 patients and a negative-control panel consisting of 790 pre-COVID-19 samples from different regions of the world. While both assays show similar diagnostic sensitivities in the early convalescent phase, ELISA 2 (featuring a higher serum concentration) enables SARS-CoV-2 IgG antibody detection for a significantly longer time postinfection (≥15 months). Correspondingly, analytical sensitivity referenced to indirect immunofluorescence testing (IIFT) is significantly higher for ELISA 2 in samples with a titer of ≤1:640; for high-titer samples, a prozone effect is observed for ELISA 2. The specificities of both ELISAs were excellent not only for pre-COVID-19 serum samples from Europe, Asia, and South America but also for several challenging African sample panels. The SARS-CoV-2 IgG FcγR ELISAs, methodically combining antigen-antibody binding in solution and isotype-specific detection of immune complexes, are valuable tools for seroprevalence studies requiring the (long-term) detection of anti-SARS-CoV-2 IgG antibodies in populations with a challenging immunological background and/or in which spike-protein-based vaccine programs have been rolled out.
Keywords: immunoassay; immunoglobulins; infectious disease; laboratory methods and tools; viral diseases.