{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,7,10]],"date-time":"2026-07-10T14:45:42Z","timestamp":1783694742064,"version":"3.55.0"},"reference-count":42,"publisher":"MDPI AG","issue":"11","license":[{"start":{"date-parts":[[2020,11,3]],"date-time":"2020-11-03T00:00:00Z","timestamp":1604361600000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Biology"],"abstract":"<jats:p>The pandemic virus SARS-CoV-2 has been reported to be able to enter the body via the eye conjunctiva, but the presence of antiviral response in the eye remains poorly known. Our study was thus aimed to analyze the presence of secretory mucosal anti-SARS-CoV-2 type A immunoglobulins (IgA) in the conjunctival fluid of COVID-19 patients. The tears of 28 COVID-19 patients and 20 uninfected controls were collected by the Schirmer test and analyzed by a specific ELISA assay detecting anti-spike (S1) virus protein IgA. The results showed that 35.7% of COVID-19 subjects have specific antiviral IgA at the ocular level, persisting till 48 days post disease onset. Most of the IgA positive subjects presented mild symptoms. The collected data indicate a prolonged persistence of anti-SARS-CoV-2 IgA at the eye level and suggest that IgA detection may be extremely helpful in clarifying virus pathology and epidemiology.<\/jats:p>","DOI":"10.3390\/biology9110374","type":"journal-article","created":{"date-parts":[[2020,11,3]],"date-time":"2020-11-03T09:09:32Z","timestamp":1604394572000},"page":"374","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":20,"title":["Anti-SARS-Cov-2 IgA Response in Tears of COVID-19 Patients"],"prefix":"10.3390","volume":"9","author":[{"ORCID":"https:\/\/orcid.org\/0000-0001-6048-9141","authenticated-orcid":false,"given":"Elisabetta","family":"Caselli","sequence":"first","affiliation":[{"name":"Department of Chemical and Pharmaceutical Sciences and LTTA, Section of Microbiology, University of Ferrara, 44121 Ferrara, Italy"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-5274-295X","authenticated-orcid":false,"given":"Irene","family":"Soffritti","sequence":"additional","affiliation":[{"name":"Department of Chemical and Pharmaceutical Sciences and LTTA, Section of Microbiology, University of Ferrara, 44121 Ferrara, Italy"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Giuseppe","family":"Lamberti","sequence":"additional","affiliation":[{"name":"Department of Biomedical and Surgical-Specialized Sciences, Ophthalmology Unit, University of Ferrara, 44121 Ferrara, Italy"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-1937-5534","authenticated-orcid":false,"given":"Maria","family":"D\u2019Accolti","sequence":"additional","affiliation":[{"name":"Department of Chemical and Pharmaceutical Sciences and LTTA, Section of Microbiology, University of Ferrara, 44121 Ferrara, Italy"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Filippo","family":"Franco","sequence":"additional","affiliation":[{"name":"Department of Biomedical and Surgical-Specialized Sciences, Ophthalmology Unit, University of Ferrara, 44121 Ferrara, Italy"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-9910-1551","authenticated-orcid":false,"given":"Davide","family":"Demaria","sequence":"additional","affiliation":[{"name":"Department of Biomedical and Surgical-Specialized Sciences, Ophthalmology Unit, University of Ferrara, 44121 Ferrara, Italy"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-2731-5809","authenticated-orcid":false,"given":"Marco","family":"Contoli","sequence":"additional","affiliation":[{"name":"Department of Morphology, Surgery and Experimental Medicine, University of Ferrara, 44121 Ferrara, Italy"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-8462-7000","authenticated-orcid":false,"given":"Angela","family":"Passaro","sequence":"additional","affiliation":[{"name":"Department of Morphology, Surgery and Experimental Medicine, University of Ferrara, 44121 Ferrara, Italy"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-8809-6470","authenticated-orcid":false,"given":"Carlo","family":"Contini","sequence":"additional","affiliation":[{"name":"Department of Medical Sciences, Infectious Diseases Unit, University of Ferrara, 44121 Ferrara, Italy"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Paolo","family":"Perri","sequence":"additional","affiliation":[{"name":"Department of Morphology, Surgery and Experimental Medicine, University of Ferrara, 44121 Ferrara, Italy"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2020,11,3]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","unstructured":"Contini, C., Caselli, E., Martini, F., Maritati, M., Torreggiani, E., Seraceni, S., Vesce, F., Perri, P., Rizzo, L., and Tognon, M. 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