title: Functional role of metaplastic paneth cell defensins in Helicobacter pylori-infected stomach.
abstract: OBJECTIVE
  Chronic gastritis is caused by Helicobacter pylori infection, and gastritis is classified as inflammation, atrophy, and intestinal metaplasia. Detailed pathologic studies have shown that H. pylori settles on the surface of gastric mucosa, and that it is eliminated from metaplastic mucosa. However, its mechanism of natural protection is not well known.
  
  
  METHODS
  Antimicrobial human enteric defensin expression was determined in the RNA and protein levels. Recombinant enteric defensins were produced with a bacterial expression system and their anti-H. pylori activities were assessed by bactericidal assay.
  
  
  RESULTS
  Human enteric defensin (HD)-5 and HD-6 were detected in Paneth cells, which are observed in the gastric metaplastic mucosa as well as small intestinal epithelia. HD-5 protein was coexpressed with trypsin, which is considered to be an activating enzyme of HD-5. Less H. pylori was observed in the intestinal metaplasia with HD-5 expressing Paneth cells. The recombinant defensins showed killing activity against H. pylori at a low concentration in vitro.
  
  
  CONCLUSIONS
  The human defensins that are expressed in the metaplastic Paneth cells eliminate H. pylori. Metaplastic change may be a purposive development of the human stomach.
authors.affiliation: Department of Internal Medicine, Division of Gastroenterology and Haematology/Oncology, Asahikawa Medical College, Asahikawa, Hokkaido, Japan. tant@asahikawa-med.ac.jp
authors.forename: Hiroki
authors.initials: H
authors.lastname: Tanabe
authors.forename: Tomonobu
authors.initials: T
authors.lastname: Sato
authors.forename: Jiro
authors.initials: J
authors.lastname: Watari
authors.forename: Atsuo
authors.initials: A
authors.lastname: Maemoto
authors.forename: Mikihiro
authors.initials: M
authors.lastname: Fujiya
authors.forename: Mikihiko
authors.initials: M
authors.lastname: Fijiya
authors.forename: Toru
authors.initials: T
authors.lastname: Kono
authors.forename: Toshifumi
authors.initials: T
authors.lastname: Ashida
authors.forename: Tokiyoshi
authors.initials: T
authors.lastname: Ayabe
authors.forename: Yutaka
authors.initials: Y
authors.lastname: Kohgo
mesh_terms: D015153:Blotting, Western; D023082:Defensins / Q000235:genetics / Q000378:metabolism* / Q000502:physiology*; D005753:Gastric Mucosa / Q000378:metabolism / Q000382:microbiology; D016481:Helicobacter Infections / Q000382:microbiology / Q000503:physiopathology*; D016480:Helicobacter pylori / Q000254:growth & development / Q000502:physiology*; D006801:Humans; D007150:Immunohistochemistry; D017403:In Situ Hybridization; D066298:In Vitro Techniques; D008679:Metaplasia / Q000378:metabolism* / Q000382:microbiology; D019879:Paneth Cells / Q000378:metabolism* / Q000382:microbiology; D011994:Recombinant Proteins; D020133:Reverse Transcriptase Polymerase Chain Reaction; D013270:Stomach / Q000166:cytology / Q000382:microbiology*
chemical_list: D023082:Defensins; D011994:Recombinant Proteins