{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,10,1]],"date-time":"2026-10-01T10:37:12Z","timestamp":1790851032974,"version":"4.1.0"},"reference-count":38,"publisher":"MDPI AG","issue":"3","license":[{"start":{"date-parts":[[2021,3,7]],"date-time":"2021-03-07T00:00:00Z","timestamp":1615075200000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"DOI":"10.13039\/501100000853","name":"University of Glasgow","doi-asserted-by":"publisher","award":["69159"],"award-info":[{"award-number":["69159"]}],"id":[{"id":"10.13039\/501100000853","id-type":"DOI","asserted-by":"publisher"}]},{"name":"IDEXX Laboratories","award":["69159"],"award-info":[{"award-number":["69159"]}]},{"DOI":"10.13039\/100005232","name":"Maddie's Fund","doi-asserted-by":"publisher","award":["69159"],"award-info":[{"award-number":["69159"]}],"id":[{"id":"10.13039\/100005232","id-type":"DOI","asserted-by":"publisher"}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Viruses"],"abstract":"<jats:p>Retroviruses belong to an important and diverse family of RNA viruses capable of causing neoplastic disease in their hosts. Feline leukaemia virus (FeLV) is a gammaretrovirus that infects domestic and wild cats, causing immunodeficiency, cytopenia and neoplasia in progressively infected cats. The outcome of FeLV infection is influenced by the host immune response; progressively infected cats demonstrate weaker immune responses compared to regressively infected cats. In this study, humoral immune responses were examined in 180 samples collected from 123 domestic cats that had been naturally exposed to FeLV, using a novel ELISA to measure antibodies recognizing the FeLV surface unit (SU) glycoprotein in plasma samples. A correlation was demonstrated between the strength of the humoral immune response to the SU protein and the outcome of exposure. Cats with regressive infection demonstrated higher antibody responses to the SU protein compared to cats belonging to other outcome groups, and samples from cats with regressive infection contained virus neutralising antibodies. These results demonstrate that an ELISA that assesses the humoral response to FeLV SU complements the use of viral diagnostic tests to define the outcome of exposure to FeLV. Together these tests could allow the rapid identification of regressively infected cats that are unlikely to develop FeLV-related disease.<\/jats:p>","DOI":"10.3390\/v13030428","type":"journal-article","created":{"date-parts":[[2021,3,7]],"date-time":"2021-03-07T21:52:15Z","timestamp":1615153935000},"page":"428","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":16,"title":["Measuring the Humoral Immune Response in Cats Exposed to Feline Leukaemia Virus"],"prefix":"10.3390","volume":"13","author":[{"ORCID":"https:\/\/orcid.org\/0000-0002-4658-6698","authenticated-orcid":false,"given":"Yasmin A.","family":"Parr","sequence":"first","affiliation":[{"name":"MRC\u2014University of Glasgow Centre for Virus Research, Glasgow, Scotland G61 1QH, UK"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Melissa J.","family":"Beall","sequence":"additional","affiliation":[{"name":"IDEXX Laboratories, Inc.\u2014Westbrook, ME 04092, USA"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-4849-288X","authenticated-orcid":false,"given":"Julie K.","family":"Levy","sequence":"additional","affiliation":[{"name":"Maddie\u2019s Shelter Medicine Program, University of Florida, Gainesville, FL 32608, USA"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Michael","family":"McDonald","sequence":"additional","affiliation":[{"name":"Veterinary Diagnostic Services, University of Glasgow, Glasgow, Scotland G61 1QH, UK"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Natascha T.","family":"Hamman","sequence":"additional","affiliation":[{"name":"Austin Pets Alive!, Austin, TX 78703, USA"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-8912-3266","authenticated-orcid":false,"given":"Brian J.","family":"Willett","sequence":"additional","affiliation":[{"name":"MRC\u2014University of Glasgow Centre for Virus Research, Glasgow, Scotland G61 1QH, UK"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-4313-5023","authenticated-orcid":false,"given":"Margaret J.","family":"Hosie","sequence":"additional","affiliation":[{"name":"MRC\u2014University of Glasgow Centre for Virus Research, Glasgow, Scotland G61 1QH, UK"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2021,3,7]]},"reference":[{"key":"ref_1","first-page":"582","article-title":"Biology of feline leukemia virus in the natural environment","volume":"36","author":"Hardy","year":"1976","journal-title":"Cancer Res."},{"key":"ref_2","doi-asserted-by":"crossref","first-page":"54","DOI":"10.1128\/iai.16.1.54-59.1977","article-title":"Passive immunity to feline leukemia: Evaluation of immunity from dams naturally infected and experimentally vaccinated","volume":"16","author":"Hoover","year":"1977","journal-title":"Infect. 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