SARS-CoV-2 Serology Status Detected by Commercialized Platforms Distinguishes Previous Infection and Vaccination Adaptive Immune Responses

Abstract

Background The severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) has infected over 110 million individuals and led to 2.5 million deaths worldwide. As more individuals are vaccinated, the clinical performance and utility of SARS-CoV-2 serology platforms needs to be evaluated. Methods The ability of four commercial SARS-CoV-2 serology platforms to detect previous infection or vaccination were evaluated using a cohort of 53 SARS-CoV-2 PCR-positive patients, 89 SARS-CoV-2-vaccinated healthcare workers (Pfizer or Moderna), and 127 SARS-CoV-2 negative patients. Serology results were compared to a cell based SARS-CoV-2 pseudovirus (PSV) neutralizing antibodies assay. Results The Roche S-(spike) antibody and Diazyme neutralizing antibodies (NAbs) assays detected adaptive immune response in 100.0% and 90.1% of vaccinated individuals who received two-doses of vaccine (initial and booster), respectively. The Roche N-(nucleocapsid) antibody assay and Diazyme IgG assay did not detect adaptive immune response in vaccinated individuals. The Diazyme Nabs assay correlated with the PSV SARS-CoV-2 ID50 neutralization titers (R2= 0.70), while correlation of the Roche S-antibody assay was weaker (R2= 0.39). Median PSV SARS-CoV-2 ID50 titers more than doubled in vaccinated individuals who received two-doses of the Moderna vaccine (ID50: 597) compared to individuals that received a single dose (ID50: 284). Conclusions The Roche S-antibody and Diazyme NAbs assays robustly detected adaptive immune responses in SARS-CoV-2 vaccinated individuals and SARS-CoV-2 infected individuals. The Diazyme NAbs assay strongly correlates with the PSV SARS-CoV-2 NAbs in vaccinated individuals. Understanding the reactivity of commercially available serology platforms is important when distinguishing vaccination response versus natural infection.

Correlation of the Commercial Anti-SARS-CoV-2 Receptor Binding Domain Antibody Test with the Chemiluminescent Reduction Neutralizing Test and Possible Detection of Antibodies to Emerging Variants

“…In the present study, results from the anti-RBD antibody test and CRNT positively correlated. This finding is consistent with previous reports ( 20 – 22 ), suggesting that the anti-RBD antibody test reflects protective immunity. In addition, CRNT and anti-RBD antibody testing successfully discriminated between symptomatic patients with COVID-19 patients in convalescence and suspected healthy individuals, suggesting that both tests are suitable for detecting SARS-CoV-2 infection.…”

Longitudinal analysis of severe acute respiratory syndrome coronavirus 2 seroprevalence using multiple serology platforms

“…As an addition to the data available about how in-house produced and commercial antibody assays respond to antibodies developed in response to infection (Amanat et al, 2021;Kanji et al, 2021;Stankov et al, 2021;Suhandynata et al, 2021), we determined how the three assays perform against vaccineinduced antibodies. We measured reactivity in serum of individuals who had received two doses of 5C).…”

Humoral and Cellular Immune Responses to Vector, Mix-and-Match, or mRNA Vaccines against SARS-CoV-2 and the Relationship between the Two Immune Responses

“…The presence of antibodies against N protein (N Ab) indicates previous infection. The presence of S Ab, RBD Ab, and/or neutralizing antibodies (NAb) indicates a prior infection with SARS-CoV-2 or a previous administration of COVID-19 vaccines ( 3 ). The activation of CD4 + T cells (helper T cells) and CD8 + T cells (cytotoxic T cells) represents the induction of cellular immune responses to previous infection or vaccinations ( 2 ).…”