{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,10,23]],"date-time":"2026-10-23T21:13:32Z","timestamp":1792790012504,"version":"4.5.0"},"reference-count":42,"publisher":"MDPI AG","issue":"2","license":[{"start":{"date-parts":[[2026,1,29]],"date-time":"2026-01-29T00:00:00Z","timestamp":1769644800000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"DOI":"10.13039\/501100012166","name":"National Key Research and Development Program of China","doi-asserted-by":"publisher","award":["2023YFC2812102"],"award-info":[{"award-number":["2023YFC2812102"]}],"id":[{"id":"10.13039\/501100012166","id-type":"DOI","asserted-by":"publisher"}]},{"name":"Ministry of Agriculture Modern Agriculture Industry Technology System Special Fund","award":["CARS-47"],"award-info":[{"award-number":["CARS-47"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Vaccines"],"abstract":"<jats:p>Objective: To develop a novel and efficient vaccine for controlling scuticociliatosis in turbot (Scophthalmus maximus), this study targeted the parasitic ciliate Pseudocohnilembus persalinus for membrane protein vaccine preparation. Methods: The immunoprotective efficacy and underlying molecular mechanisms of the vaccine were systematically evaluated through immunization\u2013challenge experiments, immune parameter detection, and transcriptomic analysis. Results: Results showed that the serum IgM level in turbot immunized with the membrane protein vaccine reached its peak one week after the second immunization, which was significantly higher than that in the control group and the whole-cell protein vaccine group (p &lt; 0.05). Additionally, the activities of serum peroxidase (POD), total superoxide dismutase (T-SOD), acetylcholinesterase (ACH), and lysozyme (LZM) were significantly enhanced (p &lt; 0.05). At 24 h and 48 h post-challenge, the relative parasite reduction rates at the wound sites in the membrane protein vaccine group were 87.79% and 74.17%, respectively. Transcriptomic analysis revealed 1063 differentially expressed genes (DEGs) in the spleen tissue of turbot immunized with the membrane protein vaccine, including 734 upregulated and 329 downregulated genes. These DEGs were significantly enriched in pathways such as glycine, serine and threonine metabolism and one carbon pool by folate, which are involved in immune responses by regulating immune cell proliferation, antioxidant defense, and immune substance synthesis. Conclusions: This study successfully developed a P. persalinus membrane protein vaccine with excellent immunoprotective efficacy and elucidated its molecular mechanisms of protection. It provides a novel vaccine candidate for the green control of turbot scuticociliatosis and offers a theoretical basis and technical support for the development of fish parasite subunit vaccines.<\/jats:p>","DOI":"10.3390\/vaccines14020142","type":"journal-article","created":{"date-parts":[[2026,1,30]],"date-time":"2026-01-30T08:19:38Z","timestamp":1769761178000},"page":"142","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":1,"title":["Development and Evaluation of Immunoprotective Efficacy of Membrane Protein Vaccine Against Scuticociliatosis"],"prefix":"10.3390","volume":"14","author":[{"given":"Qingmeihui","family":"Sun","sequence":"first","affiliation":[{"name":"Liaoning Key Laboratory of Pufferfish Breeding and Culture, Liaoning Key Laboratory of Marine Animal Immunology, Dalian Key Laboratory of Marine Animal Disease Control and Prevention, College of Fisheries and Life Science, Dalian Ocean University, Dalian 116023, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Bingchen","family":"Wu","sequence":"additional","affiliation":[{"name":"Liaoning Key Laboratory of Pufferfish Breeding and Culture, Liaoning Key Laboratory of Marine Animal Immunology, Dalian Key Laboratory of Marine Animal Disease Control and Prevention, College of Fisheries and Life Science, Dalian Ocean University, Dalian 116023, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Yaoqi","family":"Ao","sequence":"additional","affiliation":[{"name":"Liaoning Key Laboratory of Pufferfish Breeding and Culture, Liaoning Key Laboratory of Marine Animal Immunology, Dalian Key Laboratory of Marine Animal Disease Control and Prevention, College of Fisheries and Life Science, Dalian Ocean University, Dalian 116023, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Xiaoyu","family":"Meng","sequence":"additional","affiliation":[{"name":"Liaoning Key Laboratory of Pufferfish Breeding and Culture, Liaoning Key Laboratory of Marine Animal Immunology, Dalian Key Laboratory of Marine Animal Disease Control and Prevention, College of Fisheries and Life Science, Dalian Ocean University, Dalian 116023, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Xiaohang","family":"Wang","sequence":"additional","affiliation":[{"name":"Center for Animal Disease Control and Prevention in Shenyang City, Shenyang 110034, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-8385-1748","authenticated-orcid":false,"given":"Ruijun","family":"Li","sequence":"additional","affiliation":[{"name":"Liaoning Key Laboratory of Pufferfish Breeding and Culture, Liaoning Key Laboratory of Marine Animal Immunology, Dalian Key Laboratory of Marine Animal Disease Control and Prevention, College of Fisheries and Life Science, Dalian Ocean University, Dalian 116023, China"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2026,1,29]]},"reference":[{"key":"ref_1","unstructured":"Song, W., Zhao, Y., Xu, K., and Gong, J. 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