title: Polymorphisms in the intermediate region of VacA impact Helicobacter pylori-induced disease development.
abstract: Helicobacter pylori is the etiological agent of diseases such as gastritis, gastric and duodenal ulcers, and two types of gastric cancers. While some insight has been gained into the etiology of these diverse manifestations, by and large, the reason that some individuals develop more severe disease remains elusive. Recent studies have focused on the roles of H. pylori toxins CagA and VacA on the disease process and have suggested that both toxins are intimately involved. Moreover, CagA and VacA are polymorphic within different H. pylori strains, and particular polymorphisms seem to show a correlation with the development of particular disease states. Among VacA polymorphisms, the intermediate region has recently been proposed to play a major role in disease outcome. In this article, we describe a detailed sequence analysis of the polymorphic intermediate region of vacA from strains obtained from a large South Korean population. We show that polymorphisms found at amino acid position 196 are associated with more severe disease manifestations. Additionally, polymorphisms found at amino acid position 231 are linked to disease in strains that carry the non-EPIYA-ABD allele of CagA. Collectively, these data help explain the impact of the VacA intermediate region on disease and lead to the hypothesis that there are allele-driven interactions between VacA and CagA.
authors.affiliation: Department of Microbiology and Immunology, Uniformed Services University of the Health Sciences, 4301 Jones Bridge Rd., Bethesda, Maryland 20814, USA.
authors.forename: Kathleen R
authors.initials: KR
authors.lastname: Jones
authors.forename: Sungil
authors.initials: S
authors.lastname: Jang
authors.forename: Jennifer Y
authors.initials: JY
authors.lastname: Chang
authors.forename: Jinmoon
authors.initials: J
authors.lastname: Kim
authors.forename: In-Sik
authors.initials: IS
authors.lastname: Chung
authors.forename: Cara H
authors.initials: CH
authors.lastname: Olsen
authors.forename: D Scott
authors.initials: DS
authors.lastname: Merrell
authors.forename: Jeong-Heon
authors.initials: JH
authors.lastname: Cha
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D001426:Bacterial Proteins / Q000235:genetics*; D004269:DNA, Bacterial / Q000737:chemistry / Q000235:genetics; D005260:Female; D014644:Genetic Variation; D016481:Helicobacter Infections / Q000382:microbiology*; D016480:Helicobacter pylori / Q000235:genetics / Q000302:isolation & purification / Q000472:pathogenicity*; D006801:Humans; D008297:Male; D008875:Middle Aged; D008969:Molecular Sequence Data; D017422:Sequence Analysis, DNA; D037521:Virulence Factors / Q000235:genetics*; D055815:Young Adult
chemical_list: D001426:Bacterial Proteins; D004269:DNA, Bacterial; C074689:VacA protein, Helicobacter pylori; D037521:Virulence Factors