SARS-CoV-2 antibody assays are used for epidemiological studies and for the assessment of vaccine responses in highly vulnerable patients. So far, data on cross-reactivity of SARS-CoV-2 antibody assays is limited. Here, we compared four enzyme-linked immunosorbent assays (ELISAs; Vircell SARS-CoV-2 IgM/IgA and IgG, Euroimmun SARS-CoV-2 IgA and IgG) for detection of anti-SARS-CoV-2 antibodies in 207 patients with COVID-19, 178 patients with serological evidence of different bacterial infections, 107 patients with confirmed viral respiratory disease, and 80 controls from the pre-COVID-19 era. In COVID-19 patients, the assays showed highest sensitivity in week 3 (Vircell-IgM/A and Euroimmun-IgA: 78.9% each) and after week 7 (Vircell-IgG: 97.9%; Euroimmun-IgG: 92.1%). The antibody indices were higher in patients with fatal disease. In general, IgM/IgA assays had only limited or no benefit over IgG assays. In patients with non-SARS-CoV-2 respiratory infections, IgG assays were more specific than IgM/IgA assays, and bacterial infections were associated with more false-positive results than viral infections. The specificities in bacterial and viral infections were 68.0 and 81.3% (Vircell-IgM/IgA), 84.8 and 96.3% (Euroimmun-IgA), 97.8 and 86.0% (Vircell-IgG), and 97.8 and 99.1% (Euroimmun-IgG), respectively. Sera from patients positive for antibodies against Mycoplasma pneumoniae , Chlamydia psittaci , and Legionella pneumophila yielded particularly high rates of unspecific false-positive results in the IgM/IgA assays, which was revealed by applying a highly specific flow-cytometric assay using HEK 293 T cells expressing the SARS-CoV-2 spike protein. Positive results obtained with anti-SARS-CoV-2 IgM/IgA ELISAs require careful interpretation, especially if there is evidence for prior bacterial respiratory infections. Supplementary Information The online version contains supplementary material available at 10.1007/s10096-021-04285-4.
【저자키워드】 COVID-19, SARS-CoV-2, coronavirus, antibody, Bacterial infections, Euroimmun, Vircell, 【초록키워드】 respiratory infections, IgG, viral infection, T cells, anti-SARS-CoV-2, viral infections, ELISA, Spike protein, cross-reactivity, sensitivity, specificity, anti-SARS-CoV-2 antibodies, enzyme-linked immunosorbent assay, Viral, SARS-CoV-2 antibody, anti-SARS-CoV-2 antibody, vaccine response, IgA, enzyme-linked immunosorbent assays, sera, SARS-CoV-2 spike protein, Respiratory disease, Patient, Interpretation, Control, Bacterial infection, respiratory, Legionella pneumophila, disease, Bacterial infections, Euroimmun, ELISAs, COVID-19 patients, Mycoplasma pneumoniae, Bacterial, Evidence, vaccine responses, evidence of, supplementary material, epidemiological studies, Epidemiological study, pneumoniae, positive, Specificities, vulnerable patients, fatal disease, serological evidence, bacterial and viral infections, Chlamydia, bacterial respiratory infections, benefit, Cell, highest, assays, expressing, viral respiratory, false-positive result, patients with COVID-19, the SARS-CoV-2, 【제목키워드】 Viral, SARS-CoV-2 antibody, respiratory, Bacterial, viral respiratory infection, patients with COVID-19,