{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,8,31]],"date-time":"2026-08-31T12:18:15Z","timestamp":1788178695472,"version":"build-2803163510"},"reference-count":37,"publisher":"MDPI AG","issue":"22","license":[{"start":{"date-parts":[[2022,11,16]],"date-time":"2022-11-16T00:00:00Z","timestamp":1668556800000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"the Science and Technology Program of Guangzhou, China","award":["202206010161"],"award-info":[{"award-number":["202206010161"]}]},{"name":"the Science and Technology Program of Guangzhou, China","award":["2019KZDXM026"],"award-info":[{"award-number":["2019KZDXM026"]}]},{"name":"the Science and Technology Program of Guangzhou, China","award":["2020B0301030007"],"award-info":[{"award-number":["2020B0301030007"]}]},{"name":"the Key Research Projects of Universities in Guangdong Province","award":["202206010161"],"award-info":[{"award-number":["202206010161"]}]},{"name":"the Key Research Projects of Universities in Guangdong Province","award":["2019KZDXM026"],"award-info":[{"award-number":["2019KZDXM026"]}]},{"name":"the Key Research Projects of Universities in Guangdong Province","award":["2020B0301030007"],"award-info":[{"award-number":["2020B0301030007"]}]},{"name":"Guangdong Major Project of Basic and Applied Basic Research","award":["202206010161"],"award-info":[{"award-number":["202206010161"]}]},{"name":"Guangdong Major Project of Basic and Applied Basic Research","award":["2019KZDXM026"],"award-info":[{"award-number":["2019KZDXM026"]}]},{"name":"Guangdong Major Project of Basic and Applied Basic Research","award":["2020B0301030007"],"award-info":[{"award-number":["2020B0301030007"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["IJMS"],"abstract":"<jats:p>Porcine circovirus type 2 (PCV2) is capable of causing porcine circovirus-associated disease (PCVAD) and is one of the major threats to the global pig industry. The nucleocapsid protein Cap encoded by the PCV2 ORF2 gene is an ideal antigen for the development of PCV2 subunit vaccines, and its N-terminal nuclear localization sequence (NLS) structural domain is essential for the formation of self-assembling VLPs. In the present study, we systematically expressed and characterized full-length PCV2 Cap proteins fused to dominant T and B cell antigenic epitopes and porcine-derived CD154 molecules using baculovirus and found that the Cap proteins fusing epitopes were still capable of forming virus-like particles (VLPs). Both piglet and mice experiments showed that the Cap proteins fusing epitopes or paired with the molecular adjuvant CD154 were able to induce higher levels of humoral and cellular responses, particularly the secretion of PCV2-specific IFN-\u03b3 and IL-4. In addition, vaccination significantly reduced clinical signs and the viral load of PCV2 in the blood and tissues of challenged piglets. The results of the study provide new ideas for the development of a more efficient, safe and broad-spectrum next-generation PCV2 subunit vaccine.<\/jats:p>","DOI":"10.3390\/ijms232214126","type":"journal-article","created":{"date-parts":[[2022,11,16]],"date-time":"2022-11-16T02:24:53Z","timestamp":1668565493000},"page":"14126","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":17,"title":["Immunogenicity and Immunoprotection of PCV2 Virus-like Particles Incorporating Dominant T and B Cell Antigenic Epitopes Paired with CD154 Molecules in Piglets and Mice"],"prefix":"10.3390","volume":"23","author":[{"given":"Keke","family":"Wu","sequence":"first","affiliation":[{"name":"College of Veterinary Medicine, South China Agricultural University, Guangzhou 510642, China"},{"name":"Key Laboratory of Zoonosis Prevention and Control of Guangdong Province, Guangzhou 510642, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Wenshuo","family":"Hu","sequence":"additional","affiliation":[{"name":"College of Veterinary Medicine, South China Agricultural University, Guangzhou 510642, China"},{"name":"Key Laboratory of Zoonosis Prevention and Control of Guangdong Province, Guangzhou 510642, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Bolun","family":"Zhou","sequence":"additional","affiliation":[{"name":"College of Veterinary Medicine, South China Agricultural University, Guangzhou 510642, China"},{"name":"Guangdong Laboratory for Lingnan Modern Agriculture, Guangzhou 510642, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Bingke","family":"Li","sequence":"additional","affiliation":[{"name":"College of Veterinary Medicine, South China Agricultural University, Guangzhou 510642, China"},{"name":"Key Laboratory of Zoonosis Prevention and Control of Guangdong Province, Guangzhou 510642, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Xiaowen","family":"Li","sequence":"additional","affiliation":[{"name":"College of Veterinary Medicine, South China Agricultural University, Guangzhou 510642, China"},{"name":"Key Laboratory of Zoonosis Prevention and Control of Guangdong Province, Guangzhou 510642, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-7920-4115","authenticated-orcid":false,"given":"Quanhui","family":"Yan","sequence":"additional","affiliation":[{"name":"College of Veterinary Medicine, South China Agricultural University, Guangzhou 510642, China"},{"name":"Key Laboratory of Zoonosis Prevention and Control of Guangdong Province, Guangzhou 510642, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Wenxian","family":"Chen","sequence":"additional","affiliation":[{"name":"College of Veterinary Medicine, South China Agricultural University, Guangzhou 510642, China"},{"name":"Key Laboratory of Zoonosis Prevention and Control of Guangdong Province, Guangzhou 510642, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Yuwan","family":"Li","sequence":"additional","affiliation":[{"name":"College of Veterinary Medicine, South China Agricultural University, Guangzhou 510642, China"},{"name":"Key Laboratory of Zoonosis Prevention and Control of Guangdong Province, Guangzhou 510642, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Hongxing","family":"Ding","sequence":"additional","affiliation":[{"name":"College of Veterinary Medicine, South China Agricultural University, Guangzhou 510642, China"},{"name":"Key Laboratory of Zoonosis Prevention and Control of Guangdong Province, Guangzhou 510642, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Mingqiu","family":"Zhao","sequence":"additional","affiliation":[{"name":"College of Veterinary Medicine, South China Agricultural University, Guangzhou 510642, China"},{"name":"Key Laboratory of Zoonosis Prevention and Control of Guangdong Province, Guangzhou 510642, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Shuangqi","family":"Fan","sequence":"additional","affiliation":[{"name":"College of Veterinary Medicine, South China Agricultural University, Guangzhou 510642, China"},{"name":"Key Laboratory of Zoonosis Prevention and Control of Guangdong Province, Guangzhou 510642, China"},{"name":"Guangdong Laboratory for Lingnan Modern Agriculture, Guangzhou 510642, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Lin","family":"Yi","sequence":"additional","affiliation":[{"name":"College of Veterinary Medicine, South China Agricultural University, Guangzhou 510642, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Jinding","family":"Chen","sequence":"additional","affiliation":[{"name":"College of Veterinary Medicine, South China Agricultural University, Guangzhou 510642, China"},{"name":"Key Laboratory of Zoonosis Prevention and Control of Guangdong Province, Guangzhou 510642, China"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2022,11,16]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"64","DOI":"10.1038\/295064a0","article-title":"A very small porcine virus with circular single-stranded DNA","volume":"295","author":"Tischer","year":"1982","journal-title":"Nature"},{"key":"ref_2","doi-asserted-by":"crossref","first-page":"226","DOI":"10.1016\/j.vetimm.2010.05.013","article-title":"Porcine circovirus type 2 (PCV2) Cap and Rep proteins are involved in the development of cell-mediated immunity upon PCV2 infection","volume":"137","author":"Fort","year":"2010","journal-title":"Veter. 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