{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,6,8]],"date-time":"2026-06-08T06:00:02Z","timestamp":1780898402181,"version":"3.54.1"},"reference-count":20,"publisher":"Frontiers Media SA","license":[{"start":{"date-parts":[[2026,6,8]],"date-time":"2026-06-08T00:00:00Z","timestamp":1780876800000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"content-domain":{"domain":["frontiersin.org"],"crossmark-restriction":true},"short-container-title":["Front. Vet. Sci."],"abstract":"<jats:p>Polyprenyl immunostimulant (PI) was, at the time of this study, a USDA-licensed veterinary biologic for the treatment of feline rhinotracheitis. In two previous controlled challenge trials, PI administration reduced the severity of acute feline rhinotracheitis in specific pathogen-free (SPF) cats (1). We replicated the oral PI challenge-treatment protocol to evaluate humoral and virologic outcomes, measured by serum virus-neutralizing antibody titers and virus isolation, and to assess clinical ocular disease after conjunctival rechallenge. During the study, the frequency of virus isolation and the virus-neutralizing antibody (VN) titers did not vary significantly between the treatment and placebo groups. After the rechallenge, all placebo controls (8\/8) developed ocular disease, whereas 10\/16 PI-treated cats developed conjunctivitis\/ocular disease, and 6\/16 remained asymptomatic. PI treatment was associated with a 37.5% reduction in the incidence of ocular disease after conjunctival rechallenge. We hypothesize that PI may reduce the likelihood of clinical ocular disease after FeHV-1 rechallenge by priming innate cell-mediated immune responses.<\/jats:p>","DOI":"10.3389\/fvets.2026.1834777","type":"journal-article","created":{"date-parts":[[2026,6,8]],"date-time":"2026-06-08T05:36:59Z","timestamp":1780897019000},"update-policy":"https:\/\/doi.org\/10.3389\/crossmark-policy","source":"Crossref","is-referenced-by-count":0,"title":["Polyprenyl immunostimulant treatment during experimental feline herpesvirus-1 infection is associated with reduced ocular disease after conjunctival rechallenge"],"prefix":"10.3389","volume":"13","author":[{"given":"R. Eric","family":"Heidel","sequence":"first","affiliation":[{"name":"Department of Surgery, College of Medicine, University of Tennessee Health Science Center","place":["Knoxville, TN, United States"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Tanya","family":"Kuritz","sequence":"additional","affiliation":[{"name":"Sass & Sass Inc.","place":["Oak Ridge, TN, United States"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Roger K.","family":"Maes","sequence":"additional","affiliation":[{"name":"Veterinary Diagnostic Laboratory, College of Veterinary Medicine, Michigan State University","place":["East Lansing, MI, United States"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Danielle","family":"Thompson","sequence":"additional","affiliation":[{"name":"Veterinary Diagnostic Laboratory, College of Veterinary Medicine, Michigan State University","place":["East Lansing, MI, United States"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Morgan","family":"Beasley","sequence":"additional","affiliation":[{"name":"Veterinary Diagnostic Laboratory, College of Veterinary Medicine, Michigan State University","place":["East Lansing, MI, United States"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Craig R.","family":"Reinemeyer","sequence":"additional","affiliation":[{"name":"East Tennessee Clinical Research Inc.","place":["Rockwood, TN, United States"]}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1965","published-online":{"date-parts":[[2026,6,8]]},"reference":[{"key":"ref1","doi-asserted-by":"publisher","first-page":"24","DOI":"10.3389\/fvets.2017.00024","article-title":"Polyprenyl immunostimulant in feline rhinotracheitis: randomized placebo-controlled experimental and field safety studies","volume":"4","author":"Legendre","year":"2017","journal-title":"Front Vet Sci"},{"key":"ref2","doi-asserted-by":"publisher","first-page":"337","DOI":"10.1051\/vetres:2006063","article-title":"Feline herpesvirus","volume":"38","author":"Gaskell","year":"2007","journal-title":"Vet Res"},{"key":"ref3","doi-asserted-by":"publisher","first-page":"202","DOI":"10.1016\/j.tvjl.2014.05.003","article-title":"Concurrent administration of an intranasal vaccine containing feline herpesvirus-1 (FHV-1) with a parenteral vaccine containing FHV-1 is superior to parenteral vaccination alone in an acute FHV-1 challenge model","volume":"201","author":"Reagan","year":"2014","journal-title":"Vet J"},{"key":"ref4","doi-asserted-by":"publisher","first-page":"163","DOI":"10.3390\/v13020163","article-title":"Safety and efficacy of felid herpesvirus-1 deletion mutants in cats","volume":"13","author":"Lee","year":"2021","journal-title":"Viruses"},{"key":"ref5","doi-asserted-by":"publisher","first-page":"547","DOI":"10.1016\/j.jfms.2009.05.003","article-title":"Feline herpesvirus infection. 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