A High-throughput Anti-SARS-CoV-2 IgG Testing Platform for COVID-19

Du, J.; Chu, E.; Zhang, D.; Lu, C. M.; Zhang, A.; Sha, M. Y.

Background: Serology tests for detecting the antibodies to severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) can identify previous infection and help to confirm the presence of current infection. Objective: The aim of this study was to evaluate the performances of a newly developed high throughput immunoassay for anti-SARS-CoV-2 IgG antibody detection. Results: Clinical agreement studies were performed in 77 COVID-19 patient serum samples and 226 negative donor serum/plasma samples. Positive percent agreement (PPA) was 42.86% (95% CI: 9.90% to 81.59%), 55.56% (95% CI: 21.20% to 86.30%), and 96.72% (95% CI: 88.65% to 99.60%) for samples collected on 0-7 days, 8-14 days, and [≥]15 days from symptom onset, respectively. Negative Percent Agreement (NPA) was 98.23% (95% CI: 95.53% to 99.52%). No cross-reactivity was observed to patient samples positive for IgG antibodies against the following pathogens: HIV, HAV, HBV, RSV, CMV, EBV, Rubella, Influenza A, and Influenza B. Hemoglobin (200 mg/dL), bilirubin (2 mg/dL) and EDTA (10 mM) showed no significant interfering effect on this assay. Conclusion: An anti-SARS-CoV-2 IgG antibody assay with high sensitivity and specificity has been developed. With the high throughput, this assay will speed up the anti-SARS-CoV-2 IgG testing.