title: Helicobacter pylori Omp18 and its application in serologic screening of infection.
abstract: Helicobacter pylori (Hp) is a major risk factor for gastrointestinal disorders including gastric cancer. We evaluated host serum antibody responses toward outer membrane protein18 in comparison with Urease A and B subunits. omp18 and ureA-ureB gene fragments were PCR amplified, cloned, and expressed in E. coli expression system. The expressed proteins were visualized on SDS-PAGE and confirmed by immuno-blotting. Purified proteins were applied in western blotting assays in comparison with local and foreign ELISA kits. ROC curve analysis identified the optimum cut-off points for each protein. rOmp18 represented the highest rates of sensitivity (94%), specificity (89%), PPV (97.4%), NPV (77.4%), and accuracy (93.2%) in comparison with urease A and B subunits. These immunologic indices were in "substantial" agreement (Κ = 0.7) with the gold standard tests for Hp detection. This study recommends Hp conserved Omp18 as a reliable serologic marker for accurate detection of Hp infection particularly for application in population screening approaches.
authors.affiliation: Biotechnology Research Center, Pasteur Institute of Iran, No. 69, Pasteur Ave, 13164, Tehran, Iran.
authors.forename: Yeganeh
authors.initials: Y
authors.lastname: Talebkhan
authors.forename: Fatemeh
authors.initials: F
authors.lastname: Ebrahimzadeh
authors.forename: Maryam
authors.initials: M
authors.lastname: Esmaeili
authors.forename: Leili
authors.initials: L
authors.lastname: Zamaninia
authors.forename: Azin
authors.initials: A
authors.lastname: Nahvijoo
authors.forename: Hossein
authors.initials: H
authors.lastname: Khedmat
authors.forename: Forouzandeh
authors.initials: F
authors.lastname: Fereidooni
authors.forename: Mohammad Ali
authors.initials: MA
authors.lastname: Mohagheghi
authors.forename: Marjan
authors.initials: M
authors.lastname: Mohammadi
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D000907:Antibodies, Bacterial / Q000097:blood*; D000942:Antigens, Bacterial / Q000235:genetics / Q000276:immunology; D001425:Bacterial Outer Membrane Proteins / Q000235:genetics / Q000276:immunology; D001431:Bacteriological Techniques / Q000379:methods*; D015153:Blotting, Western / Q000379:methods; D003001:Cloning, Molecular; D004797:Enzyme-Linked Immunosorbent Assay / Q000379:methods; D004926:Escherichia coli / Q000235:genetics; D005260:Female; D015870:Gene Expression; D016481:Helicobacter Infections / Q000175:diagnosis*; D016480:Helicobacter pylori / Q000235:genetics / Q000276:immunology*; D006801:Humans; D008297:Male; D008875:Middle Aged; D012372:ROC Curve; D011994:Recombinant Proteins / Q000235:genetics / Q000276:immunology; D012680:Sensitivity and Specificity; D014510:Urease / Q000235:genetics; D055815:Young Adult
chemical_list: D000907:Antibodies, Bacterial; D000942:Antigens, Bacterial; D001425:Bacterial Outer Membrane Proteins; D011994:Recombinant Proteins; D014510:Urease