{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,7,30]],"date-time":"2026-07-30T09:29:09Z","timestamp":1785403749941,"version":"3.56.0"},"reference-count":30,"publisher":"MDPI AG","issue":"7","license":[{"start":{"date-parts":[[2026,7,2]],"date-time":"2026-07-02T00:00:00Z","timestamp":1782950400000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"DOI":"10.13039\/501100001809","name":"National Natural Science Foundation of China","doi-asserted-by":"publisher","award":["32302906"],"award-info":[{"award-number":["32302906"]}],"id":[{"id":"10.13039\/501100001809","id-type":"DOI","asserted-by":"publisher"}]},{"award":["32302906"],"award-info":[{"award-number":["32302906"]}],"id":[{"id":"https:\/\/ror.org\/01h0zpd94","id-type":"ROR","asserted-by":"publisher"}]},{"DOI":"10.13039\/501100018542","name":"Natural Science Foundation of Sichuan Province","doi-asserted-by":"publisher","award":["2024NSFSC1280"],"award-info":[{"award-number":["2024NSFSC1280"]}],"id":[{"id":"10.13039\/501100018542","id-type":"DOI","asserted-by":"publisher"}]},{"name":"Sichuan Province innovation team project","award":["SCCXTD-2026-24"],"award-info":[{"award-number":["SCCXTD-2026-24"]}]},{"name":"Science and Technology Department of Sichuan Province","award":["2024YFHZ0111"],"award-info":[{"award-number":["2024YFHZ0111"]}]},{"award":["2024YFHZ0111"],"award-info":[{"award-number":["2024YFHZ0111"]}],"id":[{"id":"https:\/\/ror.org\/04323m874","id-type":"ROR","asserted-by":"publisher"}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Veterinary Sciences"],"abstract":"<jats:p>Outbreaks of avian infectious bronchitis virus (IBV) often occur in vaccinated flocks. The antibody-dependent enhancement (ADE) has been proposed as a potential mechanism underlying coronavirus vaccine failure. However, this hypothesis has yet to be substantiated in flocks. This study demonstrates ADE occurrence in IBV (gamacoronavirus) in vitro and in vivo. Using the SPF chicken host model, primary infection with an O-glycosylation-modified attenuated strain enhanced pathogenesis upon secondary homologous\/heterologous virulent challenge, increasing morbidity\/mortality (\u226530%), pathological lesions, and viral loads. Notably, sequentially attenuated infections also induced ADE, suggesting live attenuated vaccine risks. The immune serum raised against the O-glycosylation-modified attenuated strain was also pre-mixed with the challenge strain, and the mixtures were then inoculated into target cells, non-susceptible macrophage cells, or a co-culture of both cell types. The serum-virus complexes replicated poorly in macrophages, yet immune cells amplified the expression of inflammatory factors and ADE-mediated viral replication in target cells, indicating a significant promoting role of immune cells in this process. The concentrations of complement component C3 and neutralizing antibodies in the immune serum were also measured, and results showed that the induction of this ADE is associated with high complement component C3 and low neutralizing antibody titers. These findings highlight risks for vaccines and antibody-based therapeutic strategies of coronavirus infection.<\/jats:p>","DOI":"10.3390\/vetsci13070650","type":"journal-article","created":{"date-parts":[[2026,7,2]],"date-time":"2026-07-02T14:51:25Z","timestamp":1783003885000},"page":"650","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":0,"title":["Occurrence of Antibody-Dependent Enhancement of Avian Infectious Bronchitis in Target Animal Experiments"],"prefix":"10.3390","volume":"13","author":[{"given":"Lin","family":"Cheng","sequence":"first","affiliation":[{"name":"College of Veterinary Medicine, Sichuan Agricultural University, Chengdu 611130, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Di","family":"Wang","sequence":"additional","affiliation":[{"name":"College of Veterinary Medicine, Sichuan Agricultural University, Chengdu 611130, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Jia-Rui","family":"Zhang","sequence":"additional","affiliation":[{"name":"College of Veterinary Medicine, Sichuan Agricultural University, Chengdu 611130, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Yi-Han","family":"Zhang","sequence":"additional","affiliation":[{"name":"College of Veterinary Medicine, Sichuan Agricultural University, Chengdu 611130, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Xin-Rui","family":"Wu","sequence":"additional","affiliation":[{"name":"College of Veterinary Medicine, Sichuan Agricultural University, Chengdu 611130, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Ya-Mei","family":"Huang","sequence":"additional","affiliation":[{"name":"College of Veterinary Medicine, Sichuan Agricultural University, Chengdu 611130, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Min","family":"Li","sequence":"additional","affiliation":[{"name":"Animal Disease Prevention and Control Center of Chengdu City, Chengdu 610000, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Fu-Yan","family":"Wang","sequence":"additional","affiliation":[{"name":"College of Veterinary Medicine, Sichuan Agricultural University, Chengdu 611130, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Yang","family":"Zhao","sequence":"additional","affiliation":[{"name":"College of Veterinary Medicine, Sichuan Agricultural University, Chengdu 611130, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Xin-Feng","family":"Han","sequence":"additional","affiliation":[{"name":"College of Veterinary Medicine, Sichuan Agricultural University, Chengdu 611130, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Min","family":"Cui","sequence":"additional","affiliation":[{"name":"College of Veterinary Medicine, Sichuan Agricultural University, Chengdu 611130, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-8897-5651","authenticated-orcid":false,"given":"Yong","family":"Huang","sequence":"additional","affiliation":[{"name":"College of Veterinary Medicine, Sichuan Agricultural University, Chengdu 611130, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-3503-8936","authenticated-orcid":false,"given":"Jing","family":"Xia","sequence":"additional","affiliation":[{"name":"College of Veterinary Medicine, Sichuan Agricultural University, Chengdu 611130, China"},{"name":"MOE Key Laboratory of Agricultural Bioinformatics, Sichuan Agricultural University, Chengdu 611130, China"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2026,7,2]]},"reference":[{"key":"ref_1","first-page":"39","article-title":"Molecular Mechanisms of Antibody-Dependent Enhancement of Viral Infection","volume":"91","author":"Filatov","year":"2026","journal-title":"Biochemistry"},{"key":"ref_2","doi-asserted-by":"crossref","first-page":"110913","DOI":"10.1016\/j.vetmic.2026.110913","article-title":"Activating FcgammaRI inhibits RIG-I-mediated host antiviral innate immunity by FGR during PRRSV-ADE infection","volume":"315","author":"Xu","year":"2026","journal-title":"Vet. 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