title: Most Helicobacter pylori-infected patients have specific antibodies, and some also have H. pylori antigens and genomic material in bile: is it a risk factor for gallstone formation?
abstract: Bile may contain a 130-kDa protein endowed with aminopeptidase activity and the ability to promote cholesterol crystallisation. As >90% of H. pylori strains have a similar peptidase activity, and half the isolates express a 110- to 140-kDa antigen, the CagA protein, we investigated a possible association between H. pylori infection and gallstones, and the presence in bile samples of factors related to H. pylori that could increase cholesterol crystallization. The prevalence of H. pylori infection was 82.1% in 112 patients with gallstones and 80.3% in 112 controls (NS). Fifteen bile samples out of 23 specimens from infected patients (65.2%) contained anti-CagA antibodies. A approximately 60-kDa antigen only reacting with an anti-CagA antibody was found in five bile samples (21.7%) from 23 infected patients. One bile sample (4.1%) contained ureA and cagA genes of H. pylori. The homology of CagA with the N-terminal sequence of aminopeptidase N was very low. We concluded that the presence of specific antibody to H. pylori in most bile samples tested and of an H. pylori putative antigen in a discrete number of cases may represent factors that increase the risk of gallstone formation.
authors.affiliation: Institute of Internal Medicine, University of Siena, Italy.
authors.forename: N
authors.initials: N
authors.lastname: Figura
authors.forename: F
authors.initials: F
authors.lastname: Cetta
authors.forename: M
authors.initials: M
authors.lastname: Angelico
authors.forename: G
authors.initials: G
authors.lastname: Montalto
authors.forename: D
authors.initials: D
authors.lastname: Cetta
authors.forename: L
authors.initials: L
authors.lastname: Pacenti
authors.forename: C
authors.initials: C
authors.lastname: Vindigni
authors.forename: D
authors.initials: D
authors.lastname: Vaira
authors.forename: F
authors.initials: F
authors.lastname: Festuccia
authors.forename: A
authors.initials: A
authors.lastname: De Santis
authors.forename: G
authors.initials: G
authors.lastname: Rattan
authors.forename: R
authors.initials: R
authors.lastname: Giannace
authors.forename: S
authors.initials: S
authors.lastname: Campagna
authors.forename: C
authors.initials: C
authors.lastname: Gennari
mesh_terms: D000907:Antibodies, Bacterial / Q000032:analysis; D000942:Antigens, Bacterial / Q000032:analysis; D001426:Bacterial Proteins / Q000032:analysis* / Q000737:chemistry; D001646:Bile / Q000382:microbiology*; D018826:CD13 Antigens / Q000737:chemistry; D016022:Case-Control Studies; D002769:Cholelithiasis / Q000453:epidemiology / Q000382:microbiology*; D005260:Female; D005798:Genes, Bacterial; D016481:Helicobacter Infections / Q000150:complications / Q000382:microbiology*; D016480:Helicobacter pylori / Q000276:immunology / Q000302:isolation & purification*; D006801:Humans; D008297:Male; D008875:Middle Aged; D015995:Prevalence; D011446:Prospective Studies; D012189:Retrospective Studies; D012307:Risk Factors
chemical_list: D000907:Antibodies, Bacterial; D000942:Antigens, Bacterial; D001426:Bacterial Proteins; C080866:cagA protein, Helicobacter pylori; D018826:CD13 Antigens