{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,10,2]],"date-time":"2026-10-02T21:00:16Z","timestamp":1790974816741,"version":"4.1.0"},"reference-count":35,"publisher":"MDPI AG","issue":"5","license":[{"start":{"date-parts":[[2024,5,16]],"date-time":"2024-05-16T00:00:00Z","timestamp":1715817600000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"UZH Global Strategy and Partnerships Funding Scheme","award":["K-53420-02 01"],"award-info":[{"award-number":["K-53420-02 01"]}]},{"name":"UZH Global Strategy and Partnerships Funding Scheme","award":["F-53130-44-01"],"award-info":[{"award-number":["F-53130-44-01"]}]},{"name":"UZH Global Strategy and Partnerships Funding Scheme","award":["F-53130-45-01"],"award-info":[{"award-number":["F-53130-45-01"]}]},{"name":"UZH Global Strategy and Partnerships Funding Scheme","award":["F-53420-10-01"],"award-info":[{"award-number":["F-53420-10-01"]}]},{"name":"UZH Scientific Research","award":["K-53420-02 01"],"award-info":[{"award-number":["K-53420-02 01"]}]},{"name":"UZH Scientific Research","award":["F-53130-44-01"],"award-info":[{"award-number":["F-53130-44-01"]}]},{"name":"UZH Scientific Research","award":["F-53130-45-01"],"award-info":[{"award-number":["F-53130-45-01"]}]},{"name":"UZH Scientific Research","award":["F-53420-10-01"],"award-info":[{"award-number":["F-53420-10-01"]}]},{"name":"Small Animal Foundation, Vetsuisse Faculty, University of Zurich","award":["K-53420-02 01"],"award-info":[{"award-number":["K-53420-02 01"]}]},{"name":"Small Animal Foundation, Vetsuisse Faculty, University of Zurich","award":["F-53130-44-01"],"award-info":[{"award-number":["F-53130-44-01"]}]},{"name":"Small Animal Foundation, Vetsuisse Faculty, University of Zurich","award":["F-53130-45-01"],"award-info":[{"award-number":["F-53130-45-01"]}]},{"name":"Small Animal Foundation, Vetsuisse Faculty, University of Zurich","award":["F-53420-10-01"],"award-info":[{"award-number":["F-53420-10-01"]}]},{"name":"Swiss Association for Small Animal","award":["K-53420-02 01"],"award-info":[{"award-number":["K-53420-02 01"]}]},{"name":"Swiss Association for Small Animal","award":["F-53130-44-01"],"award-info":[{"award-number":["F-53130-44-01"]}]},{"name":"Swiss Association for Small Animal","award":["F-53130-45-01"],"award-info":[{"award-number":["F-53130-45-01"]}]},{"name":"Swiss Association for Small Animal","award":["F-53420-10-01"],"award-info":[{"award-number":["F-53420-10-01"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Viruses"],"abstract":"<jats:p>Until recently, the diagnosis of feline infectious peritonitis (FIP) in cats usually led to euthanasia, but recent research has revealed that antiviral drugs, including the nucleoside analog GS-441524, have the potential to effectively cure FIP. Alpha-1-acid glycoprotein (AGP) has been suggested as a diagnostic marker for FIP. However, AGP quantification methods are not easily accessible. This study aimed to establish a Spatial Proximity Analyte Reagent Capture Luminescence (SPARCLTM) assay on the VetBio-1 analyzer to determine the AGP concentrations in feline serum and effusion samples. Linearity was found in serial dilutions between 1:2000 and 1:32,000; the intra-run and inter-run precision was &lt;5% and &lt;15%, respectively; and AGP was stable in serum stored for at least 8 days at room temperature, at 4 \u00b0C and at \u221220 \u00b0C. Cats with confirmed FIP had significantly higher serum AGP concentrations (median: 2954 \u00b5g\/mL (range: 200\u20135861 \u00b5g\/mL)) than those with other inflammatory diseases (median: 1734 \u00b5g\/mL (305\u20133449 \u00b5g\/mL)) and clinically healthy cats (median 235 \u00b5g\/mL (range: 78\u2013616 \u00b5g\/mL); pKW &lt; 0.0001). The AGP concentrations were significantly higher in the effusions from cats with FIP than in those from diseased cats without FIP (pMWU &lt; 0.0001). The AGP concentrations in the serum of cats with FIP undergoing GS-441524 treatment showed a significant drop within the first seven days of treatment and reached normal levels after ~14 days. In conclusion, the VetBio-1 SPARCLTM assay offers a precise, fast and cost-effective method to measure the AGP concentrations in serum and effusion samples of feline patients. The monitoring of the AGP concentration throughout FIP treatment provides a valuable marker to evaluate the treatment\u2019s effectiveness and identify potential relapses at an early stage.<\/jats:p>","DOI":"10.3390\/v16050791","type":"journal-article","created":{"date-parts":[[2024,5,16]],"date-time":"2024-05-16T03:24:48Z","timestamp":1715829888000},"page":"791","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":12,"title":["Alpha-1-Acid Glycoprotein Quantification via Spatial Proximity Analyte Reagent Capture Luminescence Assay: Application as Diagnostic and Prognostic Marker in Serum and Effusions of Cats with Feline Infectious Peritonitis Undergoing GS-441524 Therapy"],"prefix":"10.3390","volume":"16","author":[{"given":"A. Katrin","family":"Helfer-Hungerbuehler","sequence":"first","affiliation":[{"name":"Clinical Laboratory, Department of Clinical Diagnostics and Services, Center for Clinical Studies, Vetsuisse Faculty, University of Zurich, CH-8057 Zurich, Switzerland"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-9009-8256","authenticated-orcid":false,"given":"Andrea M.","family":"Spiri","sequence":"additional","affiliation":[{"name":"Clinical Laboratory, Department of Clinical Diagnostics and Services, Center for Clinical Studies, Vetsuisse Faculty, University of Zurich, CH-8057 Zurich, Switzerland"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Theres","family":"Meili","sequence":"additional","affiliation":[{"name":"Clinical Laboratory, Department of Clinical Diagnostics and Services, Center for Clinical Studies, Vetsuisse Faculty, University of Zurich, CH-8057 Zurich, Switzerland"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-2848-2091","authenticated-orcid":false,"given":"Barbara","family":"Riond","sequence":"additional","affiliation":[{"name":"Clinical Laboratory, Department of Clinical Diagnostics and Services, Center for Clinical Studies, Vetsuisse Faculty, University of Zurich, CH-8057 Zurich, Switzerland"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-6175-1153","authenticated-orcid":false,"given":"Daniela","family":"Krentz","sequence":"additional","affiliation":[{"name":"LMU Small Animal Clinic, Centre for Clinical Veterinary Medicine, LMU Munich, D-80539 Munich, Germany"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-0470-776X","authenticated-orcid":false,"given":"Katharina","family":"Zwicklbauer","sequence":"additional","affiliation":[{"name":"LMU Small Animal Clinic, Centre for Clinical Veterinary Medicine, LMU Munich, D-80539 Munich, Germany"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Katharina","family":"Buchta","sequence":"additional","affiliation":[{"name":"LMU Small Animal Clinic, Centre for Clinical Veterinary Medicine, LMU Munich, D-80539 Munich, Germany"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Anna-Maria","family":"Zuzzi-Krebitz","sequence":"additional","affiliation":[{"name":"LMU Small Animal Clinic, Centre for Clinical Veterinary Medicine, LMU Munich, D-80539 Munich, Germany"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-5256-863X","authenticated-orcid":false,"given":"Katrin","family":"Hartmann","sequence":"additional","affiliation":[{"name":"LMU Small Animal Clinic, Centre for Clinical Veterinary Medicine, LMU Munich, D-80539 Munich, Germany"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-9750-4296","authenticated-orcid":false,"given":"Regina","family":"Hofmann-Lehmann","sequence":"additional","affiliation":[{"name":"Clinical Laboratory, Department of Clinical Diagnostics and Services, Center for Clinical Studies, Vetsuisse Faculty, University of Zurich, CH-8057 Zurich, Switzerland"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-3609-2416","authenticated-orcid":false,"given":"Marina L.","family":"Meli","sequence":"additional","affiliation":[{"name":"Clinical Laboratory, Department of Clinical Diagnostics and Services, Center for Clinical Studies, Vetsuisse Faculty, University of Zurich, CH-8057 Zurich, Switzerland"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2024,5,16]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"225","DOI":"10.1016\/j.jfms.2008.09.008","article-title":"A review of feline infectious peritonitis virus infection: 1963\u20132008","volume":"11","author":"Pedersen","year":"2009","journal-title":"J. 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