title: Lack of a relationship between Lewis antigen expression and cagA, CagA, vacA and VacA status of Irish Helicobacter pylori isolates.
abstract: The cagA gene, vacA gene, CagA (cytotoxin-associated gene A product) and VacA (vacuolating cytotoxin) status of a collection of Helicobacter pylori isolates from the geographically distinct Irish population was determined, the potential association of these traits with Lewis (Le) antigen expression was assessed, and the relationship between these bacterial properties and the pathology associated with H. pylori infection was evaluated. Of the 57 isolates, a higher proportion from ulcer than from non-ulcer patients expressed VacA (71% vs. 53%). H. pylori isolates which were cagA-positive were no more significantly associated with peptic ulcers than non-ulcer disease (71% vs. 67%, P = 0.775), nor were CagA-positive isolates (57% vs. 50%, P = 0.783), but 80% of the isolates from duodenal ulcer patients were cagA-positive. Thirty-seven of the 57 isolates were tested for Le antigen expression. No statistically significant relationship (P > 0.05) was found between the occurrence and level of expression of Le(x) or Le(y) and cagA, vacA, or VacA status. This lack of an association in the Irish H. pylori isolates contrasts with that previously reported for predominantly North American isolates, and may be attributable to the adaptation of H. pylori strains with differing attributes to different human populations.
authors.affiliation: Department of Microbiology, Moyne Institute for Preventive Medicine, Trinity College, Dublin, Ireland.
authors.forename: D G
authors.initials: DG
authors.lastname: Marshall
authors.forename: S O
authors.initials: SO
authors.lastname: Hynes
authors.forename: D C
authors.initials: DC
authors.lastname: Coleman
authors.forename: C A
authors.initials: CA
authors.lastname: O'Morain
authors.forename: C J
authors.initials: CJ
authors.lastname: Smyth
authors.forename: A P
authors.initials: AP
authors.lastname: Moran
mesh_terms: D000942:Antigens, Bacterial; D001426:Bacterial Proteins / Q000235:genetics / Q000378:metabolism; D005798:Genes, Bacterial / Q000235:genetics; D016481:Helicobacter Infections / Q000150:complications / Q000276:immunology*; D016480:Helicobacter pylori / Q000235:genetics* / Q000276:immunology*; D006801:Humans; D007983:Lewis Blood Group Antigens / Q000378:metabolism*
chemical_list: D000942:Antigens, Bacterial; D001426:Bacterial Proteins; D007983:Lewis Blood Group Antigens; C074689:VacA protein, Helicobacter pylori; C080866:cagA protein, Helicobacter pylori