{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,7,30]],"date-time":"2026-07-30T09:36:41Z","timestamp":1785404201663,"version":"3.56.0"},"reference-count":20,"publisher":"MDPI AG","issue":"4","license":[{"start":{"date-parts":[[2026,4,16]],"date-time":"2026-04-16T00:00:00Z","timestamp":1776297600000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"DOI":"10.13039\/100012547","name":"Natural Science Foundation of Guangxi Zhuang Autonomous Region","doi-asserted-by":"crossref","award":["2019GXNSFAA245069"],"award-info":[{"award-number":["2019GXNSFAA245069"]}],"id":[{"id":"10.13039\/100012547","id-type":"DOI","asserted-by":"crossref"}]},{"name":"Health Commission of Guangxi Zhuang Autonomous Region","award":["Z-M20241815"],"award-info":[{"award-number":["Z-M20241815"]}]},{"award":["Z-M20241815"],"award-info":[{"award-number":["Z-M20241815"]}],"id":[{"id":"https:\/\/ror.org\/01x9sys47","id-type":"ROR","asserted-by":"publisher"}]},{"name":"Youjiang Medical University for Nationalities","award":["yy2024ky045"],"award-info":[{"award-number":["yy2024ky045"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["TropicalMed"],"abstract":"<jats:p>Background: Cysteine proteases of Clonorchis sinensis are potential diagnostic antigens, yet the performance of individual members within this diverse enzyme family requires systematic evaluation. This study aimed to assess the diagnostic potential of four recombinant cysteine proteases (rCsCP1\u20134) for human clonorchiasis. Methods: An indirect ELISA was developed to measure serum reactivity (IgG, IgG subclasses, IgA) against rCsCP1\u20134. The assay was validated using 180 microscopy-confirmed positive and 148 negative control sera. Samples were randomly split into training and validation sets (7.5:2.5). Diagnostic performance of single antigens and their combinations was evaluated using univariate and multivariate logistic regression and compared with a commercial kit. Key metrics included the area under the curve (AUC), sensitivity, specificity, accuracy, F1-score, and Kappa coefficient. Results: Four single antigen\u2013antibody pairs showed high performance: rCsCP1-IgG4 (AUC = 0.928), rCsCP2-IgA (AUC = 0.863), rCsCP3-IgG1 (AUC = 0.920), and rCsCP4-IgG4 (AUC = 0.958). Among these, rCsCP1-IgG4, rCsCP3-IgG1, and rCsCP4-IgG4 outperformed the commercial kit, achieving higher sensitivity (92.0%, 96.0%, 96.0% vs. 86.0%), specificity (87.5%, 81.3%, 90.6% vs. 78.1%), accuracy (92.0%, 88.9%, 94.1% vs. 86.0%), and F1-scores (0.902, 0.902, 0.939 vs. 0.829). The Kappa values for rCsCP1-IgG4 (0.768) and rCsCP4-IgG4 (0.773) indicated substantial agreement with the microscopic standard. Multi-antigen combinations (triple or quadruple) further enhanced performance, achieving sensitivity and specificity &gt; 98% with an AUC approaching 1.0. Conclusions: This study identifies rCsCP1 and rCsCP4, particularly in combination with IgG4 detection, as highly promising diagnostic targets for clonorchiasis. Multi-antigen combinations significantly improved diagnostic performance compared to single-antigen assays, offering a strategy for high-precision diagnosis. Furthermore, the efficacy of the rCsCP2-IgA pair suggests that detecting fecal secretory IgA could be a novel avenue for non-invasive, self-testing applications.<\/jats:p>","DOI":"10.3390\/tropicalmed11040103","type":"journal-article","created":{"date-parts":[[2026,4,16]],"date-time":"2026-04-16T07:37:19Z","timestamp":1776325039000},"page":"103","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":0,"title":["Systematic Evaluation of Four Cysteine Proteases (CsCP1\u20134) from Clonorchis sinensis for Serodiagnosis: From Single-Antigen Screening to Multi-Antigen Modeling"],"prefix":"10.3390","volume":"11","author":[{"ORCID":"https:\/\/orcid.org\/0000-0001-7280-7047","authenticated-orcid":false,"given":"Shuai","family":"Wei","sequence":"first","affiliation":[{"name":"Department of Clinical Laboratory, Hechi Hospital Affiliated to Youjiang Medical University for Nationalities (The People\u2019s Hospital of Hechi), Key Laboratory of Foodborne Trematode Research and Prevention of Health Commission of Hechi, Hechi 547000, China"},{"name":"Modern Industrial College of Biomedicine and Great Health, Youjiang Medical University for Nationalities, Baise 533000, China"},{"name":"Parasitology Department, School of Basic Medical Sciences, Guangxi Medical University, Nanning 530021, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Xinyan","family":"Chen","sequence":"additional","affiliation":[{"name":"Department of Clinical Laboratory, the First Affiliated Hospital of Guangxi Medical University, Key Laboratory of Clinical Laboratory Medicine of Guangxi Department of Education, Nanning 530021, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Shangkun","family":"Cai","sequence":"additional","affiliation":[{"name":"Gastrointestinal Surgery, Hechi Hospital Affiliated to Youjiang Medical University for Nationalities, Hechi 547000, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Xiaoqin","family":"Li","sequence":"additional","affiliation":[{"name":"Parasitology Department, School of Basic Medical Sciences, Guangxi Medical University, Nanning 530021, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Ting","family":"Lu","sequence":"additional","affiliation":[{"name":"Parasitology Department, School of Basic Medical Sciences, Guangxi Medical University, Nanning 530021, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Yaoting","family":"Li","sequence":"additional","affiliation":[{"name":"Parasitology Department, School of Basic Medical Sciences, Guangxi Medical University, Nanning 530021, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Yuanlin","family":"Hou","sequence":"additional","affiliation":[{"name":"Parasitology Department, School of Basic Medical Sciences, Guangxi Medical University, Nanning 530021, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Yanwen","family":"Li","sequence":"additional","affiliation":[{"name":"Parasitology Department, School of Basic Medical Sciences, Guangxi Medical University, Nanning 530021, China"},{"name":"Key Laboratory of Basic Research on Regional Diseases (Guangxi Medical University), Education Department of Guangxi Zhuang Autonomous Region, Nanning 530021, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Yunliang","family":"Shi","sequence":"additional","affiliation":[{"name":"Parasitology Department, School of Basic Medical Sciences, Guangxi Medical University, Nanning 530021, China"},{"name":"Key Laboratory of Basic Research on Regional Diseases (Guangxi Medical University), Education Department of Guangxi Zhuang Autonomous Region, Nanning 530021, China"},{"name":"University Engineering Research Center of Advanced Technologies in Medical and Biological Intelligent Manufacturing of Guangxi, Nanning 530021, China"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2026,4,16]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"321","DOI":"10.1016\/S1470-2045(09)70096-8","article-title":"A review of human carcinogens\u2014Part B: Biological agents","volume":"10","author":"Bouvard","year":"2009","journal-title":"Lancet Oncol."},{"key":"ref_2","doi-asserted-by":"crossref","first-page":"105320","DOI":"10.1016\/j.actatropica.2019.105320","article-title":"Surveillance of clonorchiasis in China in 2016","volume":"203","author":"Zhu","year":"2020","journal-title":"Acta Trop."},{"key":"ref_3","doi-asserted-by":"crossref","unstructured":"McCarthy, J.S., Lustigman, S., Yang, G.J., Barakat, R.M., Garc\u00eda, H.H., Sripa, B., Willingham, A.L., Prichard, R.K., and Bas\u00e1\u00f1ez, M.G. 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