Study of Helicobacter pullorum proinflammatory Properties on human epithelial cells in vitro
Gut. 2008-06-25; 58(5): 629-635
Lire sur PubMed
1. Gut. 2009 May;58(5):629-35. doi: 10.1136/gut.2007.144501. Epub 2008 Jun 25.
Study of Helicobacter pullorum proinflammatory properties on human epithelial
cells in vitro.
Varon C(1), Duriez A, Lehours P, Ménard A, Layé S, Zerbib F, Mégraud F, Laharie
(1)INSERM U853, Bordeaux, France.
BACKGROUND AND AIMS: Helicobacter pullorum is an enterohepatic Helicobacter
species of avian origin detected in patients with acute diarrhoea and
inflammatory bowel disease. The aim of the present study was to determine whether
H pullorum exerts a direct effect on human intestinal epithelial cells in vitro
and to characterise the bacterial mechanisms and the signalling pathways
MATERIALS AND METHODS: The proinflammatory properties of H pullorum from human
and avian origins were measured on human gastric (AGS) and intestinal (CaCo-2 and
HT-29) epithelial cell lines after co-culture with different H pullorum strains,
and the extent of nuclear factor-kappaB (NF-kappaB) involvement was determined.
RESULTS: All of the H pullorum strains tested stimulated interleukin 8 (IL8)
secretion by the three cell lines. Similar results were obtained with heat-killed
H pullorum. Incubation of cells with filtered H pullorum culture supernatants did
not stimulate IL8 secretion. The same observation was made when bacterial
adherence was inhibited by Transwell inserts. H pullorum induced NF-kappaB
activation and rapid nuclear translocation as demonstrated by immunofluorescent
staining and cellular fractionation. NF-kappaB involvement was confirmed by using
the specific inhibitor SN50 and small interfering RNA (siRNA) which abolished H
pullorum-induced IL8 production.
CONCLUSIONS: H pullorum strains stimulate IL8 secretion by human gastric and
intestinal epithelial cell lines. This effect requires bacterial adherence and
probably lipopolysaccharides, and is mediated by NF-kappaB signalling. The
present study strengthens the argument that H pullorum is a potent human pathogen
and highlights its putative role in acute and chronic digestive diseases such as
inflammatory bowel disease.
PMID: 18579667 [Indexed for MEDLINE]