{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,4,24]],"date-time":"2026-04-24T05:36:02Z","timestamp":1777008962904,"version":"3.51.4"},"reference-count":42,"publisher":"MDPI AG","issue":"4","license":[{"start":{"date-parts":[[2026,4,13]],"date-time":"2026-04-13T00:00:00Z","timestamp":1776038400000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"Huoying Shi","award":["National Key R&D Program of China: 2023YFE0123500 and 2023YFD1800204-4"],"award-info":[{"award-number":["National Key R&D Program of China: 2023YFE0123500 and 2023YFD1800204-4"]}]},{"name":"Huoying Shi","award":["Natural Science Foundation of Jiangsu Province (BK20230576)"],"award-info":[{"award-number":["Natural Science Foundation of Jiangsu Province (BK20230576)"]}]},{"name":"Huoying Shi","award":["The National Natural Science Foundation of China (32302823, 32172802, 32002301, 31672516, 31172300, 30670079)"],"award-info":[{"award-number":["The National Natural Science Foundation of China (32302823, 32172802, 32002301, 31672516, 31172300, 30670079)"]}]},{"name":"Huoying Shi","award":["the Priority Academic Program Development of Jiangsu Higher Education Institutions (PAPD) and supported by the 111 Project D18007"],"award-info":[{"award-number":["the Priority Academic Program Development of Jiangsu Higher Education Institutions (PAPD) and supported by the 111 Project D18007"]}]},{"name":"Yu-an Li","award":["Jiangsu Excellent Postdoctoral Program (2023ZB275)"],"award-info":[{"award-number":["Jiangsu Excellent Postdoctoral Program (2023ZB275)"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Biomolecules"],"abstract":"<jats:p>Necrotizing enteritis (NE) is an important intestinal disease threatening the poultry farming industry, and the ban on antibiotic growth promoters has created an urgent demand for safe and effective NE vaccines. Recombinant attenuated Salmonella vectors (RASVs) administered orally can induce mucosal immune responses against delivered antigens, thus showing great potential to elicit protective immunity against NE. The EntB protein is a newly discovered putative enterotoxin of Clostridium perfringens (C. perfringens). Bioinformatic predictions in this study revealed that EntB contains nineteen potential antigenic epitopes, two functional domains (NlpC and YgiM), and interacts with ten proteins, supporting its potential as a target antigen for NE vaccines. To optimize the immunogenicity of EntB-based vaccines, we constructed a novel recombinant attenuated Salmonella Enteritidis (S. Enteritidis) vector rSC0169 harboring a rhamnose-regulated delayed attenuation system, which was then used to deliver EntB to generate the recombinant strain rSC0169(pS-EntB). This system enhanced the immunogenicity of the Salmonella vector rSC0169 and further elicited robust mucosal immune responses against EntB, as well as humoral and cellular immune responses. Compared with the control strain rSC0169(pS0018), rSC0169(pS-EntB) candidate vaccine strain significantly alleviated NE symptoms, increased the intestinal villus height\/crypt depth (VH\/CD) ratio, upregulated tight junction protein expression, and reduced excessive pro-inflammatory cytokine production. In conclusion, this study provides a promising NE candidate vaccine and offers a valuable strategy for developing vaccines against other intestinal bacterial diseases.<\/jats:p>","DOI":"10.3390\/biom16040575","type":"journal-article","created":{"date-parts":[[2026,4,13]],"date-time":"2026-04-13T13:12:26Z","timestamp":1776085946000},"page":"575","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":0,"title":["Recombinant Attenuated Salmonella Enteritidis Vector Enhances the Immunogenicity of Clostridium perfringens EntB Antigen for Effective Prevention of Avian Necrotic Enteritis"],"prefix":"10.3390","volume":"16","author":[{"given":"Wenjing","family":"Li","sequence":"first","affiliation":[{"name":"College of Veterinary Medicine, Yangzhou University, Yangzhou 225009, China"},{"name":"Jiangsu Co-Innovation Center for the Prevention and Control of Important Animal Infectious Diseases and Zoonoses, Yangzhou 225009, China"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Yu-An","family":"Li","sequence":"additional","affiliation":[{"name":"College of Veterinary Medicine, Yangzhou University, Yangzhou 225009, China"},{"name":"Jiangsu Co-Innovation Center for the Prevention and Control of Important Animal Infectious Diseases and Zoonoses, Yangzhou 225009, China"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Xiaolong","family":"Liu","sequence":"additional","affiliation":[{"name":"College of Veterinary Medicine, Yangzhou University, Yangzhou 225009, China"},{"name":"Jiangsu Co-Innovation Center for the Prevention and Control of Important Animal Infectious Diseases and Zoonoses, Yangzhou 225009, China"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Haiping","family":"Xie","sequence":"additional","affiliation":[{"name":"College of Veterinary Medicine, Yangzhou University, Yangzhou 225009, China"},{"name":"Jiangsu Co-Innovation Center for the Prevention and Control of Important Animal Infectious Diseases and Zoonoses, Yangzhou 225009, China"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Jingyi","family":"Zhao","sequence":"additional","affiliation":[{"name":"College of Veterinary Medicine, Yangzhou University, Yangzhou 225009, China"},{"name":"Jiangsu Co-Innovation Center for the Prevention and Control of Important Animal Infectious Diseases and Zoonoses, Yangzhou 225009, China"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Yi","family":"Feng","sequence":"additional","affiliation":[{"name":"College of Veterinary Medicine, Yangzhou University, Yangzhou 225009, China"},{"name":"Jiangsu Co-Innovation Center for the Prevention and Control of Important Animal Infectious Diseases and Zoonoses, Yangzhou 225009, China"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Huoying","family":"Shi","sequence":"additional","affiliation":[{"name":"College of Veterinary Medicine, Yangzhou University, Yangzhou 225009, China"},{"name":"Jiangsu Co-Innovation Center for the Prevention and Control of Important Animal Infectious Diseases and Zoonoses, Yangzhou 225009, China"},{"name":"Joint International Research Laboratory of Agriculture and Agri-Product Safety, Yangzhou University, Yangzhou 225009, China"}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"1968","published-online":{"date-parts":[[2026,4,13]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"104436","DOI":"10.1016\/j.psj.2024.104436","article-title":"Identification of immunogenic antigens and evaluation of vaccine candidates against Clostridium perfringens","volume":"103","author":"Li","year":"2024","journal-title":"Poult. 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