Keywords
Key points
- •Early in the coronavirus disease 2019 (COVID-19) pandemic, the release of poorly characterized antibody tests caused concern about the quality of serologic results and a national discussion about test performance.
- •The positive predictive value of COVID-19 serologic tests varies with seroprevalence and is a major concern.
- •The kinetics of the antibody response to severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) are characterized by the appearance of immunoglobulin (Ig) G in most individuals by at least 2 weeks after symptom onset, slightly after IgM and IgA.
- •There is continued uncertainty about the significance of antibody tests in terms of the degree and durability of immunity.
- •The differential and quantitative detection of viral antigens may prove to be important and will require the development of test platforms to answer these nuanced questions.
Introduction
- Infantino M.
- Grossi V.
- Lari B.
- et al.
Viral antigens




Antibody kinetics
- Woo P.C.
- Lau S.K.
- Wong B.H.
- et al.
Test validation
Current clinical testing options
Manufacturer | Antigen | Ab Class | Format | Sensitivity (%) | Specificity (%) | Platform |
---|---|---|---|---|---|---|
Abbott | NP | IgG | CLIA | 100.0 | 99–99.6 | Architect/Alinity |
Roche | NP | IgG | ECLIA | 100.0 | 99.8 | Elecsys |
Ortho | S | IgG, Tot Ab | CLIA | 90–100 | 100.0 | Vitros |
Diasorin | S1/S2 | IgG | CMIA | 97.6 | 99.3 | Liaison XL |
Euroimmun | S1 | IgG | ELISA | 90.0 | 97.8–100 | None |
Wadsworth | NP | Tot Ab | MIA | 88.0 | 98.8 | FlexMap |
Mt Sinai | RBD and S | IgG | 2-step ELISA | 92.5 | 100.0 | None |
Cellex | NP and S | IgG and IgM | LFA | 93.8 | 96.0 | None |
Bio-Rad | NP | Tot Ab | ELISA | 92.2 | 99.6 | None |
Autobio | S | IgG and IgM | LFA | 99 | 99.0 | None |
Implications for immunity
- Has the individual been infected (if the molecular result is negative and the patient is likely outside of the window of viral shedding)?
- Does the pediatric patient have multisystem inflammatory syndrome?
- Are the infection prevention policies and personal protective equipment guidelines adequate for protecting health care workers in the institution?
- Can a recovered COVID-19 patient donate plasma for therapeutic use? What is the half-life of anti–SARS-CoV-2 antibodies in a recipient of convalescent plasma?
- Does a given serologic response indicate a successful trial vaccine?
- Has the individual mounted an adequate response to a vaccine (once one becomes available)?
Wang J, Zand MS. The potential for antibody-dependent enhancement of SARS-CoV-2 infection: Translational implications for vaccine development. Journal of Clinical and Translational Science, 1–4. https://doi.org/10.1017/cts.2020.39.
Summary
Disclosure
References
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Wang J, Zand MS. The potential for antibody-dependent enhancement of SARS-CoV-2 infection: Translational implications for vaccine development. Journal of Clinical and Translational Science, 1–4. https://doi.org/10.1017/cts.2020.39.
Article info
Publication history
Footnotes
Funding: This work was supported by the National Institutes of Health Institute of Allergy, Immunology and Infectious Diseases grants R01 AI129518 and R21 AI138500 (M.S. Zand), and the University of Rochester Clinical and Translational Science Award UL1 TR002001 from the National Center for Advancing Translational Sciences of the National Institutes of Health (M.S. Zand). The content is solely the responsibility of the authors and does not necessarily represent the official views of the National Institutes of Health. None of the mentioned funders had any role in study design, data collection and analysis, decision to publish, or preparation of the article.