title: Assessment of gastric carcinoma risk associated with Helicobacter pylori may vary depending on the antigen used: CagA specific enzyme-linked immunoadsorbent assay (ELISA) versus commercially available H. pylori ELISAs.
abstract: BACKGROUND
  Previous epidemiologic studies produced inconsistent results when examining the relation between Helicobacter pylori infection and the risk of gastric carcinoma by measuring various anti-H. pylori antibodies. This study investigated the increased risk of cancer by examining different antibodies, including the specific anti-CagA antibody and antibodies from two commercially available kits.
  
  
  METHODS
  An ELISA for the detection of serum anti-CagA was established using a recombinant CagA protein that the authors previously reported. Serum anti-CagA titer was determined for 80 patients with gastric carcinoma and 80 gender- and age-matched controls. Two anti-H. pylori antibodies from the commercially available kits HEL-p (Amrad, Kew Vic, Australia) and HM-CAP (Enteric Product Inc., Westbury, NY) were also evaluated.
  
  
  RESULTS
  Anti-CagA seropositivity differed significantly between gastric carcinoma patients and controls (92.5% vs. 55.0%; P = 0. 0001), showing an odds ratio of 10.4 (95% confidence interval [CI]: 4.23-29.74). The difference was less prominent for the seropositivity of HEL-p (77.5% vs. 58.8%; P = 0.0139; odds ratio: 2. 38; 95% CI: 1.20-4.82) and insignificant for that of HM-CAP (65.0% vs. 57.5%; P = 0.4325; odds ratio: 1.30; 95% CI: 0.68-2.49).
  
  
  CONCLUSIONS
  The current study revealed that the antibody assay system used could be one important factor in the assessment of gastric carcinoma risk for patients with H. pylori.
authors.affiliation: Department of Gastroenterology, Faculty of Medicine, University of Tokyo, Tokyo, Japan.
authors.forename: S
authors.initials: S
authors.lastname: Maeda
authors.forename: H
authors.initials: H
authors.lastname: Yoshida
authors.forename: K
authors.initials: K
authors.lastname: Ogura
authors.forename: Y
authors.initials: Y
authors.lastname: Yamaji
authors.forename: T
authors.initials: T
authors.lastname: Ikenoue
authors.forename: T
authors.initials: T
authors.lastname: Mitsushima
authors.forename: H
authors.initials: H
authors.lastname: Tagawa
authors.forename: R
authors.initials: R
authors.lastname: Kawaguchi
authors.forename: K
authors.initials: K
authors.lastname: Mori
authors.forename: K i
authors.initials: Ki
authors.lastname: Mafune
authors.forename: T
authors.initials: T
authors.lastname: Kawabe
authors.forename: Y
authors.initials: Y
authors.lastname: Shiratori
authors.forename: M
authors.initials: M
authors.lastname: Omata
mesh_terms: D000328:Adult; D000368:Aged; D000942:Antigens, Bacterial / Q000032:analysis*; D001426:Bacterial Proteins / Q000276:immunology* / Q000378:metabolism; D002277:Carcinoma / Q000382:microbiology*; D016022:Case-Control Studies; D004797:Enzyme-Linked Immunosorbent Assay / Q000379:methods*; D005260:Female; D016481:Helicobacter Infections / Q000175:diagnosis*; D016480:Helicobacter pylori / Q000276:immunology*; D006801:Humans; D008297:Male; D008875:Middle Aged; D016017:Odds Ratio; D012306:Risk; D016036:Seroepidemiologic Studies; D013274:Stomach Neoplasms / Q000382:microbiology*
chemical_list: D000942:Antigens, Bacterial; D001426:Bacterial Proteins; C080866:cagA protein, Helicobacter pylori