{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,7,30]],"date-time":"2026-07-30T10:16:57Z","timestamp":1785406617908,"version":"3.56.0"},"reference-count":40,"publisher":"MDPI AG","issue":"7","license":[{"start":{"date-parts":[[2026,7,18]],"date-time":"2026-07-18T00:00:00Z","timestamp":1784332800000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"Jiangsu Province Agricultural Science and Technology Independent Innovation Fund Project","award":["CX(24)1010"],"award-info":[{"award-number":["CX(24)1010"]}]},{"award":["CX(24)1010"],"award-info":[{"award-number":["CX(24)1010"]}],"id":[{"id":"https:\/\/ror.org\/0335n2618","id-type":"ROR","asserted-by":"publisher"}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Veterinary Sciences"],"abstract":"<jats:p>Porcine circovirus 3 (PCV3) is an emerging swine pathogen associated with reproductive disorders, multisystemic inflammation, and other clinical syndromes. The capsid protein (Cap), the principal structural and immunogenic component, is an ideal antigen for serological detection. However, its poor solubility in prokaryotic expression systems limits diagnostic assay development. In this study, the N-terminal 32 amino acids of Cap were truncated, and the protein was expressed in a soluble form using the SHuffle T7 Express strain. An indirect enzyme-linked immunosorbent assay (ELISA) using purified soluble Cap as a coating antigen was established and optimized. The assay exhibited excellent specificity, with no cross-reactivity against other common swine pathogens, high sensitivity, and good repeatability, with intra- and inter-assay coefficients of variation below 10%. The cut-off value was determined, and testing of 144 porcine serum samples showed a 78.47% concordance rate with PCR, indicating good diagnostic performance. This Cap-based indirect ELISA provides a reliable, cost-effective, and high-throughput tool for large-scale serological surveillance and epidemiological monitoring of PCV3, supporting improved disease control strategies in pig populations.<\/jats:p>","DOI":"10.3390\/vetsci13070704","type":"journal-article","created":{"date-parts":[[2026,7,20]],"date-time":"2026-07-20T09:32:54Z","timestamp":1784539974000},"page":"704","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":0,"title":["Establishment of an Indirect ELISA Detection Method for Porcine Circovirus 3 Based on Soluble Cap Protein"],"prefix":"10.3390","volume":"13","author":[{"given":"Weizhen","family":"Shen","sequence":"first","affiliation":[{"name":"MOE Joint International Research Laboratory of Animal Health and Food Safety, College of Veterinary Medicine, Nanjing Agricultural University, Nanjing 210095, China"},{"name":"Key Laboratory of Animal Bacteriology, Ministry of Agriculture and Rural Affairs, Nanjing Agricultural University, Nanjing 210095, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Mengran","family":"Zhang","sequence":"additional","affiliation":[{"name":"MOE Joint International Research Laboratory of Animal Health and Food Safety, College of Veterinary Medicine, Nanjing Agricultural University, Nanjing 210095, China"},{"name":"Key Laboratory of Animal Bacteriology, Ministry of Agriculture and Rural Affairs, Nanjing Agricultural University, Nanjing 210095, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Yixiang","family":"Lian","sequence":"additional","affiliation":[{"name":"MOE Joint International Research Laboratory of Animal Health and Food Safety, College of Veterinary Medicine, Nanjing Agricultural University, Nanjing 210095, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Jiahui","family":"Xu","sequence":"additional","affiliation":[{"name":"MOE Joint International Research Laboratory of Animal Health and Food Safety, College of Veterinary Medicine, Nanjing Agricultural University, Nanjing 210095, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0009-0003-0934-9268","authenticated-orcid":false,"given":"Yunye","family":"Jiang","sequence":"additional","affiliation":[{"name":"MOE Joint International Research Laboratory of Animal Health and Food Safety, College of Veterinary Medicine, Nanjing Agricultural University, Nanjing 210095, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0009-0008-7489-6387","authenticated-orcid":false,"given":"Jing","family":"Chen","sequence":"additional","affiliation":[{"name":"MOE Joint International Research Laboratory of Animal Health and Food Safety, College of Veterinary Medicine, Nanjing Agricultural University, Nanjing 210095, China"},{"name":"Key Laboratory of Animal Bacteriology, Ministry of Agriculture and Rural Affairs, Nanjing Agricultural University, Nanjing 210095, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Jin","family":"Cui","sequence":"additional","affiliation":[{"name":"College of Veterinary Medicine, Northeast Agricultural University, 600 Changjiang Street Xiangfang District, Harbin 150030, China"},{"name":"Key Laboratory of Diagnosis and Treatment for Epizootic Diseases of Animals in Cold Regions of Heilongjiang Province, Northeast Agricultural University, 600 Changjiang Street Xiangfang District, Harbin 150030, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-7279-9489","authenticated-orcid":false,"given":"Bin","family":"Zhou","sequence":"additional","affiliation":[{"name":"MOE Joint International Research Laboratory of Animal Health and Food Safety, College of Veterinary Medicine, Nanjing Agricultural University, Nanjing 210095, China"},{"name":"Key Laboratory of Animal Bacteriology, Ministry of Agriculture and Rural Affairs, Nanjing Agricultural University, Nanjing 210095, China"},{"name":"College of Veterinary Medicine, Northeast Agricultural University, 600 Changjiang Street Xiangfang District, Harbin 150030, China"},{"name":"Key Laboratory of Diagnosis and Treatment for Epizootic Diseases of Animals in Cold Regions of Heilongjiang Province, Northeast Agricultural University, 600 Changjiang Street Xiangfang District, Harbin 150030, China"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2026,7,18]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"2915","DOI":"10.1111\/tbed.14185","article-title":"What do we know about porcine circovirus 3 (PCV3) diagnosis so far?: A review","volume":"68","author":"Tan","year":"2021","journal-title":"Transbound. 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