Dataset Information

Evaluation of a Novel Multiplex Platform for Simultaneous Detection of IgG Antibodies against the Four Main SARS-CoV-2 Antigens.

ABSTRACT:

Background

Numerous serology assays are available for detection of SARS-CoV-2 antibodies but are limited in that only one/two target antigen(s) can be tested at a time. Here, we describe a novel multiplex assay that simultaneously detects and quantifies IgG antibodies to SARS-CoV-2 antigens, spike (S), nucleocapsid (N), receptor-binding domain (RBD), and N-terminal domain (NTD) in a single well.

Methods

Sensitivity was determined using samples (n = 124) from confirmed SARS-CoV-2 RT-PCR positive individuals. Pre-pandemic (n = 100) and non-COVID respiratory infection positive samples (n = 100) were used to evaluate specificity. Samples were analyzed using COVID-19 IgG multiplex serology assay from Meso Scale Discovery (MSD) and using commercial platforms from Abbott, EUROIMMUN, and Siemens.

Results

At > 14 days post-PCR, MSD assay displayed >98.0% sensitivity (S: 100%, 95% CI, 98.0%-100.0%; N: 98.0%, 95% CI, 97.2%-98.9%; RBD: 94.1%, 95% CI, 92.6%-95.6%; NTD: 98.0%, 95% CI, 97.2%-98.9%) and 99% specificity (95% CI, 99.3%-99.7%) for antibodies to all four antigens. Parallel assessment of antibodies to more than one antigen improved the sensitivity to 100% (95% CI, 98.0%-100.0%) while maintaining 98% (95% CI, 97.6%-98.4%) specificity regardless of the combinations used. When AU/mL concentrations of IgG antibodies from the MSD assay were compared against the corresponding IgG signals acquired from the single target commercial assays, the following correlations were observed: Abbott (vs MSD N, R2=0.73), Siemens (vs MSD RBD, R2=0.92), and EUROIMMUN (vs MSD S, R2=0.82).

Conclusion

MSD assay offers an accurate and a comprehensive assessment of SARS-CoV-2 antibodies with higher sensitivity and equivalent specificity compared to the commercial IgG serology assays.

SUBMITTER: Nandakumar V

PROVIDER: S-EPMC8767881 | biostudies-literature |

REPOSITORIES: biostudies-literature

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