tetano
Editor, Senior Moderator
Clin Microbiol Infect
. 2020 Jul 31;S1198-743X(20)30446-8.
doi: 10.1016/j.cmi.2020.07.038. Online ahead of print.
Antibody response against SARS-CoV-2 spike protein and nucleoprotein evaluated by 4 automated immunoassays and 3 ELISAs
Jan Van Elslande[SUP] 1 [/SUP], Bram Decru[SUP] 1 [/SUP], Stijn Jonckheere[SUP] 2 [/SUP], Eric Van Wijngaerden[SUP] 3 [/SUP], Els Houben[SUP] 1 [/SUP], Patricia Vandecandelaere[SUP] 2 [/SUP], Christophe Indevuyst[SUP] 4 [/SUP], Melissa Depypere[SUP] 5 [/SUP], Stefanie Desmet[SUP] 5 [/SUP], Emmanuel Andr?[SUP] 5 [/SUP], Marc Van Ranst[SUP] 5 [/SUP], Katrien Lagrou[SUP] 5 [/SUP], Pieter Vermeersch[SUP] 6 [/SUP]
Affiliations
Abstract
Objectives: To determine the antibody response against SARS-CoV-2 spike protein and nucleoprotein using 4 automated immunoassays and 3 ELISAs for the detection of total Ig antibodies (Roche) or IgG (Abbott, Diasorin, Snibe, Euroimmun, Mikrogen) in COVID-19 patients.
Methods: Sensitivity and dynamic trend to seropositivity were evaluated in 233 samples from 114 patients with moderate, severe, or critical COVID-19 confirmed with PCR on nasopharyngeal swab. Specificity was evaluated in 113 samples collected before January 2020 including 24 samples from patients with non-SARS coronavirus infection.
Results: Sensitivity for all assays was 100% [95% confidence interval: 83.7-100] 3 weeks after onset of symptoms. Specificity varied between 94.7% [88.7-97.8] and 100% [96.1-100]. Calculated at the cut-offs that corresponded to a specificity of 95% and 97.5%, Roche had the highest sensitivity (85.0% [79.8-89.0] and 81.1% [76.6-85.7], p <0.05 except vs. Abbott). Seroconversion occurred on average 2 days earlier for Roche total Ig anti-N and the 2 IgG anti-N assays (Abbott and Euroimmun) than for the 2 IgG anti-S assays (Diasorin and Euroimmun) (≥50% seroconversion day 9-10 vs. day 11-12, and p <0.05 for % seropositive patients day 9-10 to 17-18). There was no significant difference in the IgG antibody time to seroconversion between critical and non-critical patients.
Conclusions: Seroconversion occurred within 3 weeks after onset of symptoms with all assays and on average 2 days earlier for assays detecting IgG or total Ig anti-N than for IgG anti-S. The specificity of assays detecting anti-N was comparable to anti-S and excellent in a challenging control population.
. 2020 Jul 31;S1198-743X(20)30446-8.
doi: 10.1016/j.cmi.2020.07.038. Online ahead of print.
Antibody response against SARS-CoV-2 spike protein and nucleoprotein evaluated by 4 automated immunoassays and 3 ELISAs
Jan Van Elslande[SUP] 1 [/SUP], Bram Decru[SUP] 1 [/SUP], Stijn Jonckheere[SUP] 2 [/SUP], Eric Van Wijngaerden[SUP] 3 [/SUP], Els Houben[SUP] 1 [/SUP], Patricia Vandecandelaere[SUP] 2 [/SUP], Christophe Indevuyst[SUP] 4 [/SUP], Melissa Depypere[SUP] 5 [/SUP], Stefanie Desmet[SUP] 5 [/SUP], Emmanuel Andr?[SUP] 5 [/SUP], Marc Van Ranst[SUP] 5 [/SUP], Katrien Lagrou[SUP] 5 [/SUP], Pieter Vermeersch[SUP] 6 [/SUP]
Affiliations
- PMID: 32745595
- DOI: 10.1016/j.cmi.2020.07.038
Abstract
Objectives: To determine the antibody response against SARS-CoV-2 spike protein and nucleoprotein using 4 automated immunoassays and 3 ELISAs for the detection of total Ig antibodies (Roche) or IgG (Abbott, Diasorin, Snibe, Euroimmun, Mikrogen) in COVID-19 patients.
Methods: Sensitivity and dynamic trend to seropositivity were evaluated in 233 samples from 114 patients with moderate, severe, or critical COVID-19 confirmed with PCR on nasopharyngeal swab. Specificity was evaluated in 113 samples collected before January 2020 including 24 samples from patients with non-SARS coronavirus infection.
Results: Sensitivity for all assays was 100% [95% confidence interval: 83.7-100] 3 weeks after onset of symptoms. Specificity varied between 94.7% [88.7-97.8] and 100% [96.1-100]. Calculated at the cut-offs that corresponded to a specificity of 95% and 97.5%, Roche had the highest sensitivity (85.0% [79.8-89.0] and 81.1% [76.6-85.7], p <0.05 except vs. Abbott). Seroconversion occurred on average 2 days earlier for Roche total Ig anti-N and the 2 IgG anti-N assays (Abbott and Euroimmun) than for the 2 IgG anti-S assays (Diasorin and Euroimmun) (≥50% seroconversion day 9-10 vs. day 11-12, and p <0.05 for % seropositive patients day 9-10 to 17-18). There was no significant difference in the IgG antibody time to seroconversion between critical and non-critical patients.
Conclusions: Seroconversion occurred within 3 weeks after onset of symptoms with all assays and on average 2 days earlier for assays detecting IgG or total Ig anti-N than for IgG anti-S. The specificity of assays detecting anti-N was comparable to anti-S and excellent in a challenging control population.