title: Expression of cytokeratins in Helicobacter pylori-associated chronic gastritis of adult patients infected with cagA+ strains: an immunohistochemical study.
abstract: OBJECTIVE
  To investigate the expression of different cytokeratins (CKs) in gastric epithelium of adult patients with chronic gastritis infected with Helicobacter pylori (H pylori) cagA+ strains.
  
  
  METHODS
  The expression of CK 7, 8, 18, 19 and 20 was studied immunohistochemically in antral gastric biopsies of 84 patients. All the CKs were immunostained in cagA+H pylori gastritis (57 cases), non-H pylori gastritis (17 cases) and normal gastric mucosa (10 cases).
  
  
  RESULTS
  In cagA+ H pylori gastritis, CK8 was expressed comparably to the normal antral mucosa from surface epithelium to deep glands. Distribution of CK18 and CK 19 was unchanged, i.e. transmucosal, but intensity of the expression was different in foveolar region in comparison to normal gastric mucosa. Cytokeratin 18 immunoreactivity was significantly higher in the foveolar epithelium of H pylori-positive gastritis compared to both H pylori-negative gastritis and controls. On the contrary, decrease in CK19 immunoreactivity occurred in foveolar epithelium of H pylori-positive gastritis. In both normal and inflamed antral mucosa without H pylori infection, CK20 was expressed strongly/moderately and homogeneously in surface epithelium and upper foveolar region, but in H pylori -induced gastritis significant decrease of expression in foveolar region was noted. Generally, in both normal antral mucosa and H pylori-negative gastritis, expression of CK7 was not observed, while in about half cagA+ H pylori-infected patients, moderate focal CK7 immunoreactivity of the neck and coiled gland areas was registered, especially in areas with more severe inflammatory infiltrate.
  
  
  CONCLUSIONS
  Alterations in expression of CK 7, 18, 19 and 20 together with normal expression of CK8 occur in antral mucosa of H pylori-associated chronic gastritis in adult patients infected with cagA+ strains. Alterations in different cytokeratins expression might contribute to weakening of epithelial tight junctions observed in H pylori-infected gastric mucosa.
authors.affiliation: Clinical Center of Serbia, Clinic for Gastroenterology and Hepatology, Koste Todorovica 6, 11000 Belgrade, Serbia and Montenegro.
authors.forename: Vera
authors.initials: V
authors.lastname: Todorovic
authors.forename: Aleksandra
authors.initials: A
authors.lastname: Sokic-Milutinovic
authors.forename: Neda
authors.initials: N
authors.lastname: Drndarevic
authors.forename: Marjan
authors.initials: M
authors.lastname: Micev
authors.forename: Olivera
authors.initials: O
authors.lastname: Mitrovic
authors.forename: Ivan
authors.initials: I
authors.lastname: Nikolic
authors.forename: Thomas
authors.initials: T
authors.lastname: Wex
authors.forename: Tomica
authors.initials: T
authors.lastname: Milosavljevic
authors.forename: Peter
authors.initials: P
authors.lastname: Malfertheiner
mesh_terms: D000328:Adult; D000942:Antigens, Bacterial / Q000032:analysis*; D001426:Bacterial Proteins / Q000032:analysis*; D002908:Chronic Disease; D005260:Female; D005753:Gastric Mucosa / Q000378:metabolism / Q000382:microbiology / Q000473:pathology; D005756:Gastritis / Q000378:metabolism* / Q000382:microbiology* / Q000473:pathology; D016481:Helicobacter Infections / Q000378:metabolism* / Q000473:pathology; D016480:Helicobacter pylori / Q000302:isolation & purification; D006801:Humans; D007150:Immunohistochemistry; D007633:Keratins / Q000378:metabolism*; D008297:Male; D008875:Middle Aged; D011446:Prospective Studies
chemical_list: D000942:Antigens, Bacterial; D001426:Bacterial Proteins; C080866:cagA protein, Helicobacter pylori; D007633:Keratins