Commercial Serology Assays Predict Neutralization Activity against SARS-CoV-2. (21st October 2020)

• Record Type: Journal Article
• Authors: Suhandynata, Raymond T; Hoffman, Melissa A; Huang, Deli; Tran, Jenny T; Kelner, Michael J; Reed, Sharon L; McLawhon, Ronald W; Voss, James E; Nemazee, David; Fitzgerald, Robert L
• Is Part Of: Clinical chemistry. Volume 67:Number 2(2021)
• Page Start: 404
• Page End: 414
• Publication Date: 2020-10-21
• Subjects: neutralizing antibodies -- COVID-19 -- serology -- immunity -- SARS-CoV-2; Clinical chemistry -- Periodicals; Pharmaceutical chemistry -- Periodicals; Biochemistry -- Periodicals; Biochimie -- Périodiques; Diagnostics biologiques -- Périodiques; Biochemistry; Clinical chemistry; Pharmaceutical chemistry; Biochemistry; Laboratory Techniques and Procedures; Klinische chemie; Periodicals; 616.075605
• DOI: 10.1093/clinchem/hvaa262
• Languages: English
• ISSNs: 0009-9147

Abstract

Abstract: Background: It is unknown whether a positive serology result correlates with protective immunity against SARS-CoV-2. There are also concerns regarding the low positive predictive value of SARS-CoV-2 serology tests, especially when testing populations with low disease prevalence. Methods: A neutralization assay was validated in a set of PCR-confirmed positive specimens and in a negative cohort. In addition, 9530 specimens were screened using the Diazyme SARS-CoV-2 IgG serology assay and all positive results ( N = 164 individuals) were reanalyzed using the neutralization assay, the Roche total immunoglobin assay, and the Abbott IgG assay. The relationship between the magnitude of a positive SARS-CoV-2 serology result and neutralizing activity was determined. Neutralizing antibody titers (50% inhibitory dilution, ID50 ) were also longitudinally monitored in patients confirmed to have SARS-CoV-2 by PCR. Results: The SARS-CoV-2 neutralization assay had a positive percentage agreement (PPA) of 96.6% with a SARS-CoV-2 PCR test and a negative percentage agreement (NPA) of 98.0% across 100 negative control individuals. ID50 neutralization titers positively correlated with all 3 clinical serology platforms. Longitudinal monitoring of hospitalized PCR-confirmed patients with COVID-19 demonstrated they made high neutralization titers against SARS-CoV-2. PPA between the Diazyme IgG assay alone and the neutralization assay was 50.6%, while combining the Diazyme IgG assay with either the Roche or Abbott platforms increased the PPA to 79.2 and 78.4%, respectively. Conclusions: These 3 clinical serology assays positively correlate with SARS-CoV-2 neutralization activity observed in patients with COVID-19. All patients confirmed SARS-CoV-2 positive by PCR develop neutralizing antibodies.