title: Patterns of Adherence of Helicobacter pylori Clinical Isolates to Epithelial Cells, and its Association with Disease and with Virulence Factors.
abstract: OBJECTIVE
  Adherence to the gastric epithelium is one of the most important steps of Helicobacter pylori to remain and cause disease. The aim of this study was to analyze whether H. pylori isolates from patients with different gastroduodenal diseases present differences in the pattern of adherence to gastric epithelial cells (AGS), in the ability to induce IL-8, and in the presence of virulence genes.
  
  
  METHODS
  We tested 75 H. pylori strains isolated from nonatrophic gastritis, gastric cancer, and duodenal ulcer patients. The adhesion pattern and IL-8 induction were determined in AGS cells, and invasion of AGS cells was studied using a gentamicin protection assay. The IL-8 levels induced were determined by ELISA.
  
  
  RESULTS
  Helicobacter pylori strains presented diffuse adherence (DA) and localized (LA) adherence patterns, similar to those described for enteropathogenic E. coli (EPEC), were observed in AGS cells. A DA pattern was observed in 57% and LA in 43% of the strains, and DA was more frequent in isolates from patients with gastric cancer (p = 0.044). Strains with a LA pattern induced higher levels of IL-8 (p = 0.042) in AGS cells.
  
  
  CONCLUSIONS
  The adherence pattern was not associated with neither invasiveness nor with the presence of virulence genes. Our study shows that H. pylori strains present adherence patterns to AGS cells resembling those observed in EPEC and that these patterns may be associated with disease and with activity on AGS cells.
authors.affiliation: Unidad de Investigación Médica en Enfermedades Infecciosas y Parasitarias UMAE, Hospital de Pediatria, IMSS., México, DF, Mexico.
authors.forename: Flor Elizabeth
authors.initials: FE
authors.lastname: Vázquez-Jiménez
authors.affiliation: Unidad de Investigación Médica en Enfermedades Infecciosas y Parasitarias UMAE, Hospital de Pediatria, IMSS., México, DF, Mexico.
authors.forename: Javier
authors.initials: J
authors.lastname: Torres
authors.affiliation: Instituto Nacional de Salud Pública, México, Morelos, Mexico.
authors.forename: Lourdes
authors.initials: L
authors.lastname: Flores-Luna
authors.affiliation: Departamento de Microbiologia, Instituto Politecnico Nacional, Escuela Nacional de Ciencias Biologicas, Mexico, DF, Mexico.
authors.forename: Silvia Giono
authors.initials: SG
authors.lastname: Cerezo
authors.affiliation: Unidad de Investigación Médica en Enfermedades Infecciosas y Parasitarias UMAE, Hospital de Pediatria, IMSS., México, DF, Mexico.
authors.forename: Margarita
authors.initials: M
authors.lastname: Camorlinga-Ponce
mesh_terms: D001422:Bacterial Adhesion; D001426:Bacterial Proteins / Q000235:genetics / Q000378:metabolism*; D004847:Epithelial Cells / Q000378:metabolism / Q000382:microbiology*; D005753:Gastric Mucosa / Q000378:metabolism / Q000382:microbiology; D016481:Helicobacter Infections / Q000382:microbiology*; D016480:Helicobacter pylori / Q000235:genetics / Q000302:isolation & purification / Q000502:physiology*; D006801:Humans; D016209:Interleukin-8 / Q000235:genetics / Q000378:metabolism; D008875:Middle Aged; D037521:Virulence Factors / Q000235:genetics / Q000378:metabolism*
chemical_list: D001426:Bacterial Proteins; D016209:Interleukin-8; D037521:Virulence Factors
keywords: AGS cells; H. pylori; Pattern of adherence; diffuse; localized