title: Study on sero-diagnosis of nasopharyngeal carcinoma using a dual antibody test against recombinant Epstein-Barr virus antigens.
abstract: OBJECTIVE
  The aim of this study was to optimize a dual-antibody assay for sero-diagnosis of nasopharyngeal carcinoma(NPC) by evaluating 4 Epstein-Barr virus(EBV) antigen-based enzyme-linked immunosorbent assays(ELISAs).
  
  
  METHODS
  The serum samples of 57 pretreated NPC patients and 58 apparently healthy adults in Guangzhou were collected. The levels of anti-EBV antibody in the sera were tested by 4 ELISAs, which were developed using fusion proteins of glutathione transferase and EBV specific recombinant antigens, namely, EBNA1-IgA, EBNA1-IgG, Zta-IgA, and Zta-IgG.
  
  
  RESULTS
  When evaluated individually, the sensitivity(0.9123) and negative predictive value(0.9074) of EBNA1-IgA were the highest among the 4 ELISAs tested. Zta-IgA test had the highest individual accuracy rate(pi, 0.8870) and Youden index(J, 0.7738). The dual positives for EBNA1-IgA and Zta-IgA were the highest among the 4 dual positives when paired ELISAs were evaluated. Five NPC patients with negative reaction to EBNA1-IgA showed positive reaction of Zta-IgA, and 7 NPC patients with negative reaction to Zta-IgA showed positive reaction of EBNA1-IgA.
  
  
  CONCLUSIONS
  The EBNA1-IgA assay is more suitable than the other 3 ELISAs(EBNA1-IgG, Zta-IgA, and Zta-IgG) when used individually for serological diagnosis of NPC. When two assays are combined, EBNA1-IgA and Zta-IgA have complementary effect on serological diagnosis for NPC and is thus an optimal combination of serum antibody assays.
authors.affiliation: Zhongshan Bio-Tech Co., Ltd., Zhongshan, Guangdong, 528437, PR China.
authors.forename: Yao-Liang
authors.initials: YL
authors.lastname: Gu
authors.forename: Chang-Qing
authors.initials: CQ
authors.lastname: Zhang
authors.forename: Sze-Park
authors.initials: SP
authors.lastname: Ng
authors.forename: Yong-Sheng
authors.initials: YS
authors.lastname: Zong
authors.forename: Ying-Jie
authors.initials: YJ
authors.lastname: Liang
authors.forename: Yue-Long
authors.initials: YL
authors.lastname: Chen
mesh_terms: D000328:Adult; D000914:Antibodies, Viral / Q000097:blood*; D004268:DNA-Binding Proteins / Q000276:immunology; D004797:Enzyme-Linked Immunosorbent Assay; D019309:Epstein-Barr Virus Nuclear Antigens / Q000276:immunology*; D006801:Humans; D007070:Immunoglobulin A / Q000097:blood; D009303:Nasopharyngeal Neoplasms / Q000175:diagnosis* / Q000821:virology; D011994:Recombinant Proteins / Q000276:immunology; D012680:Sensitivity and Specificity; D012698:Serologic Tests; D015534:Trans-Activators / Q000276:immunology; D014764:Viral Proteins / Q000276:immunology
chemical_list: D000914:Antibodies, Viral; C063676:BZLF1 protein, Herpesvirus 4, Human; D004268:DNA-Binding Proteins; D019309:Epstein-Barr Virus Nuclear Antigens; D007070:Immunoglobulin A; D011994:Recombinant Proteins; D015534:Trans-Activators; D014764:Viral Proteins; C417029:EBV-encoded nuclear antigen 1