title: Species-specific immunity to Helicobacter suis.
abstract: BACKGROUND
  Helicobacter (H.) suis is mainly associated with pigs, but is also the most prevalent gastric non-H. pylori Helicobacter species found in humans. Both H. pylori and H. suis may cause persistent infection of the stomach. Several immune evasion mechanisms have been proposed for H. pylori, which focus to a great extent on its major virulence factors, which are absent in H. suis. The aim of this study was to gain more knowledge on immune evasion by H. suis.
  
  
  METHODS
  Cytokine expression kinetics were monitored in the stomach of BALB/c mice experimentally infected with H. suis. The cytokine expression profile in the stomach of naturally H. suis-infected pigs was also determined. Subsequently, the effect of H. suis on murine and porcine dendritic cell (DC) maturation and their ability to elicit T-cell effector responses was analyzed.
  
  
  RESULTS
  Despite a Th17/Th2 response in the murine stomach, the inflammatory cell influx was unable to clear H. suis infection. H. suis-stimulated murine bone marrow-derived dendritic cells induced IL-17 secretion by CD4+cells in vitro. Natural H. suis infection in pigs evoked increased expression levels of IL-17 mRNA in the antrum and IL-10 mRNA in the fundus. In contrast to mice, H. suis-stimulated porcine monocyte-derived dendritic cells were unable to express MHCII molecules on their cell surface. These semimature DCs induced proliferation of T-cells, which showed an increased expression of TGF-β and FoxP3 mRNA levels.
  
  
  CONCLUSIONS
  Helicobacter suis might evade host immune responses by skewing toward a Treg-biased response.
authors.affiliation: Department of Pathology, Bacteriology and Avian Diseases, Faculty of Veterinary Medicine, Ghent University, Merelbeke, Belgium.
authors.forename: Iris
authors.identifier: http://orcid.org/0000-0001-9996-3509
authors.initials: I
authors.lastname: Bosschem
authors.affiliation: Department of Pathology, Bacteriology and Avian Diseases, Faculty of Veterinary Medicine, Ghent University, Merelbeke, Belgium.
authors.forename: Bram
authors.initials: B
authors.lastname: Flahou
authors.affiliation: Department of Pathology, Bacteriology and Avian Diseases, Faculty of Veterinary Medicine, Ghent University, Merelbeke, Belgium.
authors.forename: Kim
authors.initials: K
authors.lastname: Van Deun
authors.affiliation: Department of Biomedical molecular biology, Faculty of Sciences, Ghent University, Gent, Belgium.
authors.forename: Stefaan
authors.initials: S
authors.lastname: De Koker
authors.affiliation: Veterinary Research Institute, Brno, Czech Republic.
authors.forename: Jiri
authors.initials: J
authors.lastname: Volf
authors.affiliation: Department of Pathology, Bacteriology and Avian Diseases, Faculty of Veterinary Medicine, Ghent University, Merelbeke, Belgium.
authors.forename: Annemieke
authors.initials: A
authors.lastname: Smet
authors.affiliation: Department of Pathology, Bacteriology and Avian Diseases, Faculty of Veterinary Medicine, Ghent University, Merelbeke, Belgium.
authors.forename: Richard
authors.initials: R
authors.lastname: Ducatelle
authors.affiliation: Department of Virology, Parasitology, Immunology, Faculty of Veterinary Medicine, Ghent University, Merelbeke, Belgium.
authors.forename: Bert
authors.initials: B
authors.lastname: Devriendt
authors.affiliation: Department of Pathology, Bacteriology and Avian Diseases, Faculty of Veterinary Medicine, Ghent University, Merelbeke, Belgium.
authors.forename: Freddy
authors.initials: F
authors.lastname: Haesebrouck
mesh_terms: D000818:Animals; D016207:Cytokines / Q000378:metabolism; D005260:Female; D020869:Gene Expression Profiling; D016481:Helicobacter Infections / Q000276:immunology / Q000382:microbiology / Q000662:veterinary*; D018247:Helicobacter heilmannii / Q000276:immunology*; D054884:Host-Pathogen Interactions; D057131:Immune Evasion; D008807:Mice, Inbred BALB C; D013270:Stomach / Q000276:immunology / Q000382:microbiology; D013552:Swine; D013601:T-Lymphocytes / Q000276:immunology
chemical_list: D016207:Cytokines
keywords: 
  Helicobacter suis
  ; BALB/c mice; Pig; immune response