title: Serodiagnosis of Schistosoma japonicum infection: genome-wide identification of a protein marker, and assessment of its diagnostic validity in a field study in China.
abstract: BACKGROUND
  Schistosomiasis remains a highly prevalent and serious parasitic disease. A major factor preventing its effective management is the scarcity of effective diagnostic tools. We did a genome-wide identification of diagnostic protein markers for schistosome infection and assessed their diagnostic validity in a field study.
  
  
  METHODS
  We predicted putative secreted proteins of Schistosoma japonicum (SjSPs) and expressed them as glutathione S-transferase (GST)-fusion proteins. The fusion proteins were arrayed on glutathione (GSH)-immobilised microplates and screened with serum samples from patients with schistosomiasis diagnosed by the Kato-Katz method. We further assessed an identified protein marker for sensitivity and specificity, first in infected serum samples collected from Jiangxi and Hunan Provinces, China, and then through a field study, done in two villages located in a high schistosomiasis-endemic area of the southeast of China.
  
  
  RESULTS
  Of 204 recombinant proteins, 35 yielded seropositive reactions, eight showed strong immunoreactivity, and only one (SjSP-13) reacted to the entire panel of 14 archived samples. The reactivity of SjSP-13 to 476 serum samples showed 90·4% (95% CI 86·5-93·5) sensitivity and 98·9% (95% CI 95·9-99·9) specificity. Of 1371 residents enrolled in a field study from Dec 6, 2010, to June 23, 2011, only 74 individuals were identified as being egg-positive, whereas 465 were diagnosed as positive by the SjSP-13-based ELISA kit (rSP13-ELISA). Of the 394 individuals found egg-negative but rSP13-ELISA-positive, 363 (92·4%) were confirmed to be positive for schistosome infection by PCR detection of S japonicum SjR2 retrotransposon.
  
  
  CONCLUSIONS
  The application of this sensitive, specific, and affordable rSP13-ELISA method should help reduce schistosomiasis transmission through targeted treatment of individuals, particularly with low intensity infections, and therefore support schistosomiasis control and elimination strategies.
  
  
  BACKGROUND
  National 973 project in China.
authors.affiliation: Institute for Infectious Diseases and Vaccine Development, Tongji University School of Medicine, Shanghai, China.
authors.forename: Xindong
authors.initials: X
authors.lastname: Xu
authors.affiliation: Institute for Infectious Diseases and Vaccine Development, Tongji University School of Medicine, Shanghai, China.
authors.forename: Yuanbin
authors.initials: Y
authors.lastname: Zhang
authors.affiliation: Jiangxi Provincial Institute of Parasitic Diseases, Nanchang 330046, Jiangxi, China.
authors.forename: Dandan
authors.initials: D
authors.lastname: Lin
authors.affiliation: Institute for Infectious Diseases and Vaccine Development, Tongji University School of Medicine, Shanghai, China.
authors.forename: Jinjin
authors.initials: J
authors.lastname: Zhang
authors.affiliation: Department of Parasitology, Medical College of Soochow University, Suzhou, Jiangsu, China.
authors.forename: Jin
authors.initials: J
authors.lastname: Xu
authors.affiliation: Jiangxi Provincial Institute of Parasitic Diseases, Nanchang 330046, Jiangxi, China.
authors.forename: Yue-Min
authors.initials: YM
authors.lastname: Liu
authors.affiliation: Jiangxi Provincial Institute of Parasitic Diseases, Nanchang 330046, Jiangxi, China.
authors.forename: Fei
authors.initials: F
authors.lastname: Hu
authors.affiliation: Institute for Infectious Diseases and Vaccine Development, Tongji University School of Medicine, Shanghai, China.
authors.forename: Xiaoxing
authors.initials: X
authors.lastname: Qing
authors.affiliation: Department of Parasitology, Medical College of Soochow University, Suzhou, Jiangsu, China.
authors.forename: Chaoming
authors.initials: C
authors.lastname: Xia
authors.affiliation: Institute for Infectious Diseases and Vaccine Development, Tongji University School of Medicine, Shanghai, China; Department of Tropical Infectious Diseases, Second Military Medical University, Shanghai, China. Electronic address: wqpan0912@aliyun.com.
authors.forename: Weiqing
authors.initials: W
authors.lastname: Pan
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D000818:Animals; D000871:Anthelmintics / Q000627:therapeutic use; D000909:Antibodies, Helminth / Q000097:blood*; D015415:Biomarkers / Q000378:metabolism; D002648:Child; D002675:Child, Preschool; D002681:China; D004797:Enzyme-Linked Immunosorbent Assay / Q000379:methods*; D005243:Feces / Q000469:parasitology; D005260:Female; D015870:Gene Expression; D005982:Glutathione Transferase / Q000276:immunology; D015801:Helminth Proteins / Q000235:genetics / Q000276:immunology*; D006801:Humans; D008297:Male; D008875:Middle Aged; D011223:Praziquantel / Q000627:therapeutic use; D015995:Prevalence; D011993:Recombinant Fusion Proteins / Q000276:immunology; D012549:Schistosoma japonicum / Q000235:genetics / Q000276:immunology* / Q000302:isolation & purification; D012554:Schistosomiasis japonica / Q000175:diagnosis* / Q000188:drug therapy / Q000469:parasitology; D012680:Sensitivity and Specificity; D055815:Young Adult
chemical_list: D000871:Anthelmintics; D000909:Antibodies, Helminth; D015415:Biomarkers; D015801:Helminth Proteins; D011993:Recombinant Fusion Proteins; D011223:Praziquantel; D005982:Glutathione Transferase