tetano
Editor, Senior Moderator
Am J Clin Pathol
. 2021 Aug 31;aqab092.
doi: 10.1093/ajcp/aqab092. Online ahead of print.
Analytical and Clinical Evaluation of the Semiquantitative Elecsys Anti-SARS-CoV-2 Spike Protein Receptor Binding Domain Antibody Assay on the Roche cobas e602 Analyzer
Clarence W Chan[SUP] 1 [/SUP], Xin Yi[SUP] 2 3 [/SUP], Michael Lenza[SUP] 4 [/SUP], Angel D Baldwin[SUP] 4 [/SUP], Jennifer Jakalski[SUP] 4 [/SUP], Vera Tesic[SUP] 1 5 [/SUP], Kiang-Teck J Yeo[SUP] 1 4 5 [/SUP]
Affiliations
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.
. 2021 Aug 31;aqab092.
doi: 10.1093/ajcp/aqab092. Online ahead of print.
Analytical and Clinical Evaluation of the Semiquantitative Elecsys Anti-SARS-CoV-2 Spike Protein Receptor Binding Domain Antibody Assay on the Roche cobas e602 Analyzer
Clarence W Chan[SUP] 1 [/SUP], Xin Yi[SUP] 2 3 [/SUP], Michael Lenza[SUP] 4 [/SUP], Angel D Baldwin[SUP] 4 [/SUP], Jennifer Jakalski[SUP] 4 [/SUP], Vera Tesic[SUP] 1 5 [/SUP], Kiang-Teck J Yeo[SUP] 1 4 5 [/SUP]
Affiliations
- PMID: 34463315
- DOI: 10.1093/ajcp/aqab092
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.