title: Suppressed Gastric Mucosal TGF-beta1 Increases Susceptibility to H. pylori-Induced Gastric Inflammation and Ulceration: A Stupid Host Defense Response.
abstract: OBJECTIVE
  Loss of transforming growth factor beta1 (TGF-beta1) exhibits a similar pathology to that seen in a subset of individuals infected with Helicobacter pylori, including propagated gastric inflammation, oxidative stress, and autoimmune features. We thus hypothesized that gastric mucosal TGF-beta1 levels could be used to determine the outcome after H. pylori infection.
  
  
  METHODS
  Northern blot for the TGF-beta1 transcript, staining of TGF-beta1 expression, luciferase reporter assay, and enzyme-linked immunosorbent assay for TGF-beta1 levels were performed at different times after H. pylori infection.
  
  
  RESULTS
  The TGF-beta1 level was markedly lower in patients with H. pylori-induced gastritis than in patients with a similar degree of gastritis induced by nonsteroidal anti-inflammatory drugs. There was a significant negative correlation between the severity of inflammation and gastric mucosal TGF-beta1 levels. SNU-16 cells showing intact TGF-beta signaling exhibited a marked decrease in TGF-beta1 expression, whereas SNU-638 cells defective in TGF-beta signaling exhibited no such decrease after H. pylori infection. The decreased expressions of TGF-beta1 in SNU-16 cells recovered to normal after 24 hr of H. pylori infection, but lasted very spatial times, suggesting that attenuated expression of TGF-beta1 is a host defense mechanism to avoid attachment of H. pylori.
  
  
  CONCLUSIONS
  H. pylori infection was associated with depressed gastric mucosal TGF-beta1 for up to 24 hr, but this apparent strategy for rescuing cells from H. pylori attachment exacerbated the gastric inflammation.
authors.affiliation: Laboratory of Cell Regulation and Carcinogenesis, Lee Gil Ya Cancer and Diabetes Institute, Gachon University of Medicine and Science, Incheon, Korea.
authors.forename: Yunjeong
authors.initials: Y
authors.lastname: Jo
authors.forename: Sang Uk
authors.initials: SU
authors.lastname: Han
authors.forename: Yoon Jae
authors.initials: YJ
authors.lastname: Kim
authors.forename: Ju Hyeon
authors.initials: JH
authors.lastname: Kim
authors.forename: Shin Tae
authors.initials: ST
authors.lastname: Kim
authors.forename: Seong-Jin
authors.initials: SJ
authors.lastname: Kim
authors.forename: Ki-Baik
authors.initials: KB
authors.lastname: Hahm