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 involved. 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.
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 involved. 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.
Authors: S P Mane; M G Dominguez-Bello; M J Blaser; B W Sobral; R Hontecillas; J Skoneczka; S K Mohapatra; O R Crasta; C Evans; T Modise; S Shallom; M Shukla; C Varon; F Mégraud; A L Maldonado-Contreras; K P Williams; J Bassaganya-Riera Journal: J Bacteriol Date: 2010-04-16 Impact factor: 3.490
Authors: Margarida R Parente; Elena Forte; Micol Falabella; Ivo G Boneca; Miguel Teixeira; Alessandro Giuffrè; Lígia M Saraiva Journal: Sci Rep Date: 2017-08-30 Impact factor: 4.379