{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,7,14]],"date-time":"2026-07-14T06:04:39Z","timestamp":1784009079266,"version":"3.55.0"},"reference-count":39,"publisher":"Frontiers Media SA","license":[{"start":{"date-parts":[[2026,7,14]],"date-time":"2026-07-14T00:00:00Z","timestamp":1783987200000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"DOI":"10.13039\/100021177","name":"CDC Foundation","doi-asserted-by":"publisher","id":[{"id":"10.13039\/100021177","id-type":"DOI","asserted-by":"publisher"}]}],"content-domain":{"domain":["frontiersin.org"],"crossmark-restriction":true},"short-container-title":["Front. Immunol."],"abstract":"<jats:p>While humoral responses to vaccination and infection have largely focused on IgG, there is an evolving literature on ways in which IgA may drive neutrophil activity in lung injury secondary to viral infections, including COVID-19. We evaluated 238 immune-na\u00efve, critically ill patients in the first year of the COVID-19 pandemic. Employing a laboratory-developed, multiplexed antibody testing, clinical history, medical record, and machine learning, we pursued relationships between systemic IgA and disease severity. Individuals with elevated anti-N IgA had 4-fold odds of more severe disease. This work emphasizes the importance of continued work to understand how different elements of the immune system participate together in contributing to patient outcomes.<\/jats:p>","DOI":"10.3389\/fimmu.2026.1870217","type":"journal-article","created":{"date-parts":[[2026,7,14]],"date-time":"2026-07-14T05:37:06Z","timestamp":1784007426000},"update-policy":"https:\/\/doi.org\/10.3389\/crossmark-policy","source":"Crossref","is-referenced-by-count":0,"title":["Anti-SARS-CoV-2 nucleoprotein IgA is associated with worse disease severity in critically ill COVID-19 pneumonia patients"],"prefix":"10.3389","volume":"17","author":[{"given":"David M.","family":"Brett-Major","sequence":"first","affiliation":[{"name":"Department of Epidemiology, College of Public Health, University of Nebraska Medical Center","place":["Omaha, NE, United States"]},{"name":"Division of Infectious Diseases, Department of Medicine, College of Medicine, University of Nebraska Medical Center","place":["Omaha, NE, United States"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Dylan S.","family":"George","sequence":"additional","affiliation":[{"name":"Department of Pathology, Microbiology, and Immunology, College of Medicine, University of Nebraska Medical Center","place":["Omaha, NE, United States"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Eric D.","family":"Morrell","sequence":"additional","affiliation":[{"name":"Division of Pulmonary Critical Care and Sleep Medicine, University of Washington Medical Center","place":["Seattle, WA, United States"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Carmen","family":"Mikacenic","sequence":"additional","affiliation":[{"name":"Benaroya Research Institute, Virginia Mason Franciscan Health","place":["Seattle, WA, United States"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Julie M.","family":"Carstens","sequence":"additional","affiliation":[{"name":"Department of Pathology, Microbiology, and Immunology, College of Medicine, University of Nebraska Medical Center","place":["Omaha, NE, United States"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Laura E.","family":"Evans","sequence":"additional","affiliation":[{"name":"Division of Pulmonary Critical Care and Sleep Medicine, University of Washington Medical Center","place":["Seattle, WA, United States"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Mark M.","family":"Wurfel","sequence":"additional","affiliation":[{"name":"Division of Pulmonary Critical Care and Sleep Medicine, University of Washington Medical Center","place":["Seattle, WA, United States"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Pavan K.","family":"Bhatraju","sequence":"additional","affiliation":[{"name":"Division of Pulmonary Critical Care and Sleep Medicine, University of Washington Medical Center","place":["Seattle, WA, United States"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"M. 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