Longitudinal SARS-CoV-2 antibody study using the Easy Check COVID-19 IgM/IgG™ lateral flow assay.

Abstract

Since the initial identification of the novel coronavirus SARS-CoV-2 in December of 2019, researchers have raced to understand its pathogenesis and begun devising vaccine and treatment strategies. An accurate understanding of the body's temporal immune response against SARS-CoV-2 is paramount to successful vaccine development and disease progression monitoring. To provide insight into the antibody response against SARS-CoV-2, plasma samples from 181 PCR-confirmed COVID-19 patients collected at various timepoints post-symptom onset (PSO) were tested for the presence of anti-SARS-CoV-2 IgM and IgG antibodies via lateral flow. Additionally, 21 donors were tracked over time to elucidate patient-specific immune responses. We found sustained levels of anti-SARS-CoV-2 antibodies past 130 days PSO, with 99% positivity observed at 31-60 days PSO. By 61-90 days PSO, the percentage of IgM-/IgG+ results were nearly equal to that of IgM+/IgG+ results, demonstrating a shift in the immune response with a decrease in IgM antibody levels. Results from this study not only provide evidence that the antibody response to COVID-19 can persist for over 4 months, but also demonstrates the ability of Easy Check™ to monitor seroconversion and antibody response of patients. Easy Check was sufficiently sensitive to detect antibodies in patient samples as early as 1-4 days PSO with 86% positivity observed at 5-7 days PSO. Further studies are required to determine the longevity and efficacy of anti-SARS-CoV-2 antibodies, and whether they are protective against re-infection.

• Authors: Renee L Higgins, Stephen A Rawlings, Jamie Case, Florence Y Lee, Clarence W Chan, Bethany Barrick, Zoe C Burger, Kiang-Teck J Yeo, Dena Marrinucci
• Journal: PloS one (PLoS One) Vol. 16 Issue 3 Pg. e0247797 ( 2021) ISSN: 1932-6203 [Electronic] United States
• PMID: 33661960 (Publication Type: Journal Article)

Chemical References

• Antibodies, Viral
• Immunoglobulin G
• Immunoglobulin M

Topics

• Adolescent
• Adult
• Aged
• Aged, 80 and over
• Antibodies, Viral (blood, immunology)
• COVID-19 (blood, immunology)
• COVID-19 Serological Testing (instrumentation, methods)
• Equipment Design
• Female
• Humans
• Immunoglobulin G (blood, immunology)
• Immunoglobulin M (blood, immunology)
• Longitudinal Studies
• Male
• Middle Aged
• SARS-CoV-2 (immunology, isolation & purification)
• Young Adult