{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,10,23]],"date-time":"2026-10-23T20:53:58Z","timestamp":1792788838714,"version":"4.5.0"},"reference-count":52,"publisher":"Frontiers Media SA","license":[{"start":{"date-parts":[[2026,9,23]],"date-time":"2026-09-23T00:00:00Z","timestamp":1790121600000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"DOI":"10.13039\/501100003725","name":"National Research Foundation of Korea","doi-asserted-by":"publisher","award":["RS-2026-2548073022182102130001"],"award-info":[{"award-number":["RS-2026-2548073022182102130001"]}],"id":[{"id":"10.13039\/501100003725","id-type":"DOI","asserted-by":"publisher"}]},{"name":"Global-Learning & Academic research institution for Master, PhD students, and Postdocs (G-LAMP) Program of the National Research Foundation of Korea","award":["RS-2023-00301850"],"award-info":[{"award-number":["RS-2023-00301850"]}],"id":[{"id":"https:\/\/ror.org\/013aysd81","id-type":"ROR","asserted-by":"crossref"}]}],"content-domain":{"domain":["frontiersin.org"],"crossmark-restriction":true},"short-container-title":["Front. Vet. Sci."],"abstract":"<jats:sec>\n                    <jats:title>Introduction<\/jats:title>\n                    <jats:p>Fowl adenovirus serotype 4 (FAdV-4) causes fatal hepatitis in chickens and has a substantial impact on the poultry industry. The virus primarily targets the liver in chickens. Although viral load in the brain has been previously reported, the association of acute FAdV-4 infection with brain immune response remains poorly characterized. Therefore, this study focuses on immune alterations in the brain during acute FAdV-4 infection.<\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec>\n                    <jats:title>Methods<\/jats:title>\n                    <jats:p>Here, we investigated an increase in immune cell populations, along with the expression of barrier-related genes, to define the neuroimmune response during FAdV-4 infection.<\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec>\n                    <jats:title>Results<\/jats:title>\n                    <jats:p>\n                      Our results demonstrated that there was an alteration in the immune cell population, characterized by an increased frequencies of activated monocytes\/macrophages and T cell subsets in the brain from infected chickens. Additionally, the CD44\n                      <jats:sup>+<\/jats:sup>\n                      CD8\n                      <jats:sup>+<\/jats:sup>\n                      and \u03b3\u03b4 CD8\n                      <jats:sup>+<\/jats:sup>\n                      were elevated among T cell subsets and accompanied by a surge in\n                      <jats:italic>TNFA<\/jats:italic>\n                      mRNA expression. The alteration was extended to the low expression of genes encoding tight-junction (TJ) proteins, such as\n                      <jats:italic>TJP1, CLDN5,<\/jats:italic>\n                      and\n                      <jats:italic>OCLN<\/jats:italic>\n                      , and a depletion in CLDN5 protein levels. This downregulation corresponded to the detection of FAdV-4 hexon DNA in the chicken brain homogenates from the infected group, suggesting a potential link between structural barrier alterations and viral presence.\n                    <\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec>\n                    <jats:title>Discussion<\/jats:title>\n                    <jats:p>Together, these findings suggest acute FAdV-4 infection-associated neuroimmune alterations, mapping a distinct immunophenotypic and transcriptional landscape within the avian brain.<\/jats:p>\n                  <\/jats:sec>","DOI":"10.3389\/fvets.2026.1964202","type":"journal-article","created":{"date-parts":[[2026,9,23]],"date-time":"2026-09-23T10:48:23Z","timestamp":1790160503000},"update-policy":"https:\/\/doi.org\/10.3389\/crossmark-policy","source":"Crossref","is-referenced-by-count":0,"title":["Neuroimmune responses in the chicken brain during acute fowl adenovirus serotype 4 infection"],"prefix":"10.3389","volume":"13","author":[{"given":"Ulfiani Fauzia","family":"Hanafi","sequence":"first","affiliation":[{"name":"College of Veterinary Medicine, Kangwon National University","place":["Chuncheon, Gangwon-Do, Republic of Korea"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Rangyeon","family":"Lee","sequence":"additional","affiliation":[{"name":"College of Veterinary Medicine, Kangwon National University","place":["Chuncheon, Gangwon-Do, Republic of Korea"]},{"name":"Multidimensional Genomics Research Center, Kangwon National University","place":["Chuncheon, Gangwon-Do, Republic of Korea"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Kyungseok","family":"Shin","sequence":"additional","affiliation":[{"name":"College of Veterinary Medicine, Kangwon National University","place":["Chuncheon, Gangwon-Do, Republic of Korea"]},{"name":"Multidimensional Genomics Research Center, Kangwon National University","place":["Chuncheon, Gangwon-Do, Republic of Korea"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Yoon-Beom","family":"Lee","sequence":"additional","affiliation":[{"name":"Multidimensional Genomics Research Center, Kangwon National University","place":["Chuncheon, Gangwon-Do, Republic of Korea"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Geelsu","family":"Hwang","sequence":"additional","affiliation":[{"name":"Department of Preventive and Restorative Sciences, School of Dental Medicine, University of Pennsylvania","place":["Philadelphia, PA, United States"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Lilik","family":"Maslachah","sequence":"additional","affiliation":[{"name":"Department of Veterinary Basic Medicine, Faculty of Veterinary Medicine, Universitas Airlangga","place":["Surabaya, East Java, Indonesia"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Jeongho","family":"Park","sequence":"additional","affiliation":[{"name":"College of Veterinary Medicine, Kangwon National University","place":["Chuncheon, Gangwon-Do, Republic of Korea"]},{"name":"Multidimensional Genomics Research Center, Kangwon National University","place":["Chuncheon, Gangwon-Do, Republic of Korea"]}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1965","published-online":{"date-parts":[[2026,9,23]]},"reference":[{"key":"ref1","doi-asserted-by":"publisher","first-page":"388","DOI":"10.3390\/v13030388","article-title":"Adenovirus core proteins: structure and function","volume":"13","author":"Kulanayake","year":"2021","journal-title":"Viruses"},{"key":"ref2","doi-asserted-by":"publisher","first-page":"432","DOI":"10.1007\/s11262-025-02160-4","article-title":"Molecular characterization and evolutionary analysis of human adenovirus type 55, related to febrile respiratory illness 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