title: Antibodies Against Epstein-Barr Virus Glycoprotein gp42 for the Diagnosis of Nasopharyngeal Carcinoma.
abstract: BACKGROUND
  Assessment of immunoglobulin A (IgA) antibody responses to Epstein-Barr virus (EBV) antigen is important for the early diagnosis of nasopharyngeal carcinoma (NPC). EBV glycoprotein gp42 has been shown to play an essential role in membrane fusion with B cells. The aim of the present study was to assess whether the antibodies to EBV glycoprotein gp42 in serum could be a novel marker for diagnosis of NPC.
  
  
  METHODS
  EBV glycoprotein gp42 expressed in the recombinant baculovirus system was used in an enzyme-linked immunosorbent assay (ELISA) to detect antibodies to gp42 in serum. The blood samples were obtained from 406 participants (n = 208 patients with NPC and 198 healthy controls). Receiver operating characteristics (ROC) was used to calculate diagnostic accuracy.
  
  
  RESULTS
  The ROC curves showed that IgA-gp42 ELISA had a sensitivity of 76.4%, specificity of 78.3% and an area under the curve (AUC) of 0.856 (95% CI, 0.82 - 0.891) to diagnose NPC. Furthermore, gp42 maintained diag- nostic capacity in NPC patients who were IgA-viral capsid antigen (VCA) negative (87.5%, 64.1% and 0.844 [95% CI, 0.776 - 0.912]). Combining gp42 and VCA improved the diagnostic capacity compared with the individual tests (89.9%, 94.4% and 0.973 [95% CI, 0.959 - 0.9871).
  
  
  CONCLUSIONS
  The EBV glycoprotein complex gp42 acts as a novel biomarker for diagnosis of NPC and improves identification of patients with VCA-negative NPC.
authors.forename: Rui-Chen
authors.initials: RC
authors.lastname: Li
authors.forename: Yong
authors.initials: Y
authors.lastname: Du
authors.forename: Qiu-Yao
authors.initials: QY
authors.lastname: Zeng
authors.forename: Lin-Quan
authors.initials: LQ
authors.lastname: Tang
authors.forename: Hua
authors.initials: H
authors.lastname: Zhang
authors.forename: Yan
authors.initials: Y
authors.lastname: Li
authors.forename: Wan-Li
authors.initials: WL
authors.lastname: Liu
authors.forename: Qian
authors.initials: Q
authors.lastname: Zhong
authors.forename: Mu-Sheng
authors.initials: MS
authors.lastname: Zeng
authors.forename: Xiao-Ming
authors.initials: XM
authors.lastname: Huang
mesh_terms: D000328:Adult; D000914:Antibodies, Viral / Q000097:blood*; D015415:Biomarkers; D036022:Capsid Proteins / Q000032:analysis; D002277:Carcinoma; D005260:Female; D006023:Glycoproteins / Q000276:immunology*; D006801:Humans; D007070:Immunoglobulin A / Q000097:blood; D016015:Logistic Models; D008297:Male; D008875:Middle Aged; D000077274:Nasopharyngeal Carcinoma; D009303:Nasopharyngeal Neoplasms / Q000175:diagnosis* / Q000821:virology; D012372:ROC Curve; D014764:Viral Proteins / Q000276:immunology*
chemical_list: D000914:Antibodies, Viral; C101688:BZLF2 protein, Herpesvirus 4, Human; D015415:Biomarkers; D036022:Capsid Proteins; D006023:Glycoproteins; D007070:Immunoglobulin A; D014764:Viral Proteins