Abstract
Objectives: To analytically and clinically evaluate the semiquantitative Elecsys anti-severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) spike protein antibody (S-Ab) assay on the Roche cobas e602 analyzer.
Methods: The S-Ab assay is a 1-step, double-antigen sandwich electrochemiluminescent immunoassay that semiquantitatively measures total IgG, IgM, and IgA antibodies specific for the receptor binding domain of SARS-CoV-2 spike protein in serum or plasma. The S-Ab assay was evaluated for precision, linearity, interference (by hemoglobin, bilirubin, triglycerides, and biotin), cross-reactivity, and clinical performance, and was compared to the qualitative Elecsys anti-nucleocapsid (N-Ab) immunoassay, a lateral flow device that qualitatively detects S-Ab and N-Ab, and an anti-spike enzyme-linked immunosorbent assay (ELISA).
Results: S-Ab assay is precise, exhibits linearity from 0.4 to 250 U/mL, is unaffected by significant cross-reactivity or interferences, and qualitatively demonstrates greater than 90% concordance with N-Ab assay and lateral flow device. Readouts of S-Ab assay correlate with ELISA, which in turn correlates strongly with SARS-CoV-2 virus neutralization assay, and exhibit 100% sensitivity and specificity for COVID-19 patient samples obtained at or more than 14 days after PCR positivity.
Conclusions: The S-Ab assay is a robust clinical test for qualitative and semiquantitative detection of seropositivity following SARS-CoV-2 infection or spike-encoding mRNA COVID-19 vaccination.
Keywords: Anti-spike antibodies; Antibodies; COVID-19; Coronavirus; Diagnostics; Immunoassay; SAR-CoV-2; Semiquantitative; Serology; Spike protein.
【저자키워드】 COVID-19, antibodies, coronavirus, SAR-CoV-2, serology, diagnostics, spike protein., immunoassay, anti-spike antibodies, Semiquantitative, 【초록키워드】 SARS-CoV-2, IgG, IgM, coronavirus, SAR-CoV-2, spike, serology, antibody, SARS-COV-2 infection, SARS-CoV-2 virus, ELISA, Spike protein, Receptor binding domain, cross-reactivity, Protein, immunoassay, serum, enzyme-linked immunosorbent assay, Concordance, Lateral flow device, COVID-19 vaccination, Sensitivity and specificity, Neutralization assay, mRNA, SARS-CoV-2 spike protein, Seropositivity, plasma, hemoglobin, respiratory, Roche, anti-spike antibodies, Anti-spike, PCR positivity, Biotin, triglycerides, Bilirubin, COVID-19 patient, Interference, linearity, acute respiratory syndrome, Precision, acute respiratory syndrome coronavirus, IgA antibodies, measure, enzyme-linked immunosorbent, robust, greater, detect, evaluate, clinically, evaluated, turn, exhibit, IgA antibody, Elecsy, semiquantitatively, 【제목키워드】 spike, clinical, Roche, Analyzer, Elecsy,