Serodiagnostic antigens of Clonorchis sinensis identified and evaluated by high-throughput proteogenomics.

• Main Authors: Pyo Yun Cho, Ji-Yun Lee, Tae Im Kim, Jin-Ho Song, Sung-Jong Hong, Won Gi Yoo, Takafumi Tsuboi, Kwon-Soo Ha, Jae-Wan Jung, Satoru Takeo, Eun-Taek Han, Banchob Sripa, Sung-Tae Hong, Jong-Yil Chai, Ho-Woo Nam, Jhang Ho Pak, Tong-Soo Kim
• Format: Article
• Language: English
• Published: Public Library of Science (PLoS) 2020-12-01
• Series: PLoS Neglected Tropical Diseases
• Online Access: https://doi.org/10.1371/journal.pntd.0008998
• ISSN: 1935-2727; 1935-2735

Clonorchiasis caused by Clonorchis sinensis is endemic in East Asia; approximately 15 million people have been infected thus far. To diagnose the infection, serodiagnostic tests with excellent functionality should be performed. First, 607 expressed sequence tags encoding polypeptides with a secretory signal were expressed into recombinant proteins using an in vitro translation system. By protein array-based screening using C. sinensis-infected sera, 18 antigen candidate proteins were selected and assayed for cross-reactivity against Opisthorchis viverrini-infected sera. Of the six antigenic proteins selected, four were synthesized on large scale in vitro and evaluated for antigenicity against the flukes-infected human sera using ELISA. CsAg17 antigen showed the highest sensitivity (77.1%) and specificity (71.2%). The sensitivity and specificity of the bacterially produced CsAg17-28GST fusion antigen was similar to those of CsAg17 antigen. CsAg17 antigen can be used to develop point-of-care serodiagnostic tests for clonorchiasis.