{"doi":"10.1093/infdis/jiab222","title":"A Combination of N and S Antigens With IgA and IgG Measurement Strengthens the Accuracy of SARS-CoV-2 Serodiagnostics","abstract":"BACKGROUND: Primary diagnosis of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection is based on detection of virus RNA in nasopharyngeal swab samples. In addition, analysis of humoral immunity against SARS-CoV-2 has an important role in viral diagnostics and seroprevalence estimates. METHODS: We developed and optimized an enzyme immunoassays (EIA) using SARS-CoV-2 nucleoprotein (N), S1 and receptor binding domain (RBD) of the viral spike protein, and N proteins from SARS, Middle East respiratory syndrome (MERS), and 4 low-pathogenic human CoVs. Neutralizing antibody activity was compared with SARS-CoV-2 IgG, IgA, and IgM EIA results. RESULTS: The sensitivity of EIA for detecting immune response in COVID-19 patients (n = 101) was 77% in the acute phase and 100% in the convalescent phase of SARS-CoV-2 infection when N and RBD were used as antigens in IgG and IgA specific EIAs. SARS-CoV-2 infection significantly increased humoral immune responses against the 229E and NL63 N proteins. S1 and RBD-based EIA results had a strong correlation with microneutralization test results. CONCLUSIONS: The data indicate a combination of SARS-CoV-2 S1 or RBD and N proteins and analysis of IgG and IgA immunoglobulin classes in sera provide an excellent basis for specific and sensitive serological diagnostics of COVID-19.","journal":"The Journal of Infectious Diseases","year":2021,"id":165734,"datarank":0.0,"base_score":0.0,"endowment":0.0,"self_citation_contribution":0.0,"citation_network_contribution":0.0,"self_endowment_contribution":0.0,"citer_contribution":0.0,"corpus_percentile":null,"corpus_rank":null,"citation_count":35,"citer_count":0,"citers_with_citation_signal":0,"citers_with_endowment":0,"datacite_reuse_total":0,"is_dataset":false,"is_dataset_confidence":0.9647,"is_data_producer":false,"deposit_databanks":null,"is_oa":true,"file_count":0,"downloads":0,"has_version_chain":false,"published_date":"2021-01-01","fair_score":null,"fair_percentile":null,"algorithm_id":"datarank_citation_only_1hop_v6","ranking_scope":"data_only","authors":[{"id":654708,"name":"Arja Pasternack","orcid":"0000-0002-6088-4245","position":1,"is_corresponding":false},{"id":689602,"name":"Sari Maljanen","orcid":"0000-0002-3056-7249","position":2,"is_corresponding":false},{"id":690240,"name":"Krister Melén","orcid":null,"position":3,"is_corresponding":false},{"id":689603,"name":"Pekka Kolehmainen","orcid":"0000-0001-5997-8167","position":4,"is_corresponding":false},{"id":689604,"name":"Moona Huttunen","orcid":"0000-0002-4745-0477","position":5,"is_corresponding":false},{"id":689605,"name":"Rickard Lundberg","orcid":"0009-0002-1873-5964","position":6,"is_corresponding":false},{"id":689606,"name":"Lav Tripathi","orcid":"0000-0002-7388-9280","position":7,"is_corresponding":false},{"id":689607,"name":"Hira Khan","orcid":"0000-0002-9972-6607","position":8,"is_corresponding":false},{"id":690241,"name":"Mikael A. Ritvos","orcid":null,"position":9,"is_corresponding":false},{"id":689608,"name":"Rauno Naves","orcid":"0000-0001-7473-0637","position":10,"is_corresponding":false},{"id":689609,"name":"Anu Haveri","orcid":"0000-0003-4620-7536","position":11,"is_corresponding":false},{"id":689610,"name":"Pamela Österlund","orcid":"0000-0002-2229-6661","position":12,"is_corresponding":false},{"id":689611,"name":"Suvi Kuivanen","orcid":"0000-0002-2347-5397","position":13,"is_corresponding":false},{"id":689612,"name":"Anne J. 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