title: Gastric epithelial expression of macrophage migration inhibitory factor is not altered by Helicobacter pylori infection in humans.
abstract: BACKGROUND
  Recent reports have shown an upregulation of macrophage migration inhibitory factor (MIF) during gastric ulcer development in a rat model and elevated counts of MIF-positive cells in biopsies from Helicobacter pylori-infected patients. H. pylori infection is a proven cofactor in humans causing gastritis and gastric ulcers. The aim of this study was to characterize MIF expression in human gastric epithelial cells in response to H. pylori.
  
  
  METHODS
  MIF mRNA and MIF protein expression was detected in human gastric epithelial cell lines after stimulation with proinflammatory cytokines or infection with H. pylori (cagA+/vacA+) using real-time reverse transcriptase-polymerase and enzyme-linked immunosorbent assay. Interleukin-8 secretion was measured as positive control. MIF mRNA and MIF protein expression was assessed in H. pylori-positive and -negative human gastric biopsy samples.
  
  
  RESULTS
  While interleukin-8 mRNA expression and interleukin-8 secretion were upregulated in gastric epithelial cells in vitro after H. pylori infection, no changes in MIF mRNA expression and MIF secretion could be detected. We found no significant differences in MIF expression in total RNA extracted from gastric biopsy tissue when comparing H. pylori-positive to control patients. Likewise, MIF protein expression in gastric epithelium was unaffected by H. pylori infection as compared to uninfected tissue.
  
  
  CONCLUSIONS
  While an increased MIF expression and positive effects of MIF blockade in ulcer healing have been shown in a rodent model and elevated numbers of MIF-positive cells have been found in H. pylori-infected human tissue, we herein could not confirm any differences in human gastric epithelial MIF expression and secretion after H. pylori infection in vitro and in vivo.
authors.affiliation: Department of Medicine B, University of Muenster, Albert-Schweitzer-Strasse 33, D-48129 Muenster, Germany. lebiedzp@uni-muenster.de
authors.forename: Pia
authors.initials: P
authors.lastname: Lebiedz
authors.forename: Jan
authors.initials: J
authors.lastname: Heidemann
authors.forename: Andreas
authors.initials: A
authors.lastname: Lugering
authors.forename: Susanne
authors.initials: S
authors.lastname: Riedel
authors.forename: Hermann
authors.initials: H
authors.lastname: Herbst
authors.forename: Wolfram
authors.initials: W
authors.lastname: Domschke
authors.forename: Torsten
authors.initials: T
authors.lastname: Kucharzik
authors.forename: Christian
authors.initials: C
authors.lastname: Maaser
mesh_terms: D001706:Biopsy; D002460:Cell Line; D004797:Enzyme-Linked Immunosorbent Assay; D004848:Epithelium / Q000276:immunology / Q000378:metabolism / Q000382:microbiology; D005753:Gastric Mucosa / Q000276:immunology / Q000378:metabolism* / Q000382:microbiology; D005786:Gene Expression Regulation; D016481:Helicobacter Infections / Q000276:immunology* / Q000378:metabolism; D016480:Helicobacter pylori / Q000276:immunology*; D006801:Humans; D016209:Interleukin-8 / Q000096:biosynthesis; D008263:Macrophage Migration-Inhibitory Factors / Q000096:biosynthesis*; D012333:RNA, Messenger / Q000032:analysis; D020133:Reverse Transcriptase Polymerase Chain Reaction
chemical_list: D016209:Interleukin-8; D008263:Macrophage Migration-Inhibitory Factors; D012333:RNA, Messenger