AIMS: The evaluation of the effects of Enterococcus hirae, an intestinal bacterium in the adjacent mucosa (mucosal bacterium), on tumour necrosis factor-alpha (TNF-alpha)-induced barrier impairment in human epithelial Caco-2 cells. METHODS AND RESULTS: The filter-grown Caco-2 monolayers were used as an intestinal epithelial model system. In Caco-2 cells, heat-killed E. hirae ATCC 9790(T) suppressed the TNF-alpha-induced barrier impairment and increase in interleukin-8 (IL-8) secretion, but lipase- and mutanolysin-treated E. hirae ATCC 9790(T) did not have these effects. It was demonstrated that lipoteichoic acid (LTA) from E. hirae ATCC 9790(T) is responsible for Caco-2 cells' recovery from TNF-alpha-induced impairments. In addition, Caco-2 cells had the same response to Toll-like receptor 2 (TLR2) ligand, Pam(3)Cys-Ser-(Lys)(4) as they did to LTA. Increased expression of zonula occludens-1 was observed by the addition of E. hirae ATCC 9790(T) to TNF-alpha-treated Caco-2 cells, and decreased expression of myosin light chain kinase was observed by the addition of LTA and Pam(3)Cys-Ser-(Lys)(4); this, in turn, led to barrier enforcement. CONCLUSIONS: Enterococcus hirae ATCC 9790(T) cell wall fractions, such as LTA, protect against intestinal impairment by regulation of epithelial tight junction via TLR2 signalling. SIGNIFICANCE AND IMPACT OF THE STUDY: Enterococcus hirae could be useful in the treatment of inflammatory bowel disease, as well as other intestinal disorders.
AIMS: The evaluation of the effects of Enterococcus hirae, an intestinal bacterium in the adjacent mucosa (mucosal bacterium), on tumour necrosis factor-alpha (TNF-alpha)-induced barrier impairment in human epithelial Caco-2 cells. METHODS AND RESULTS: The filter-grown Caco-2 monolayers were used as an intestinal epithelial model system. In Caco-2 cells, heat-killed E. hirae ATCC 9790(T) suppressed the TNF-alpha-induced barrier impairment and increase in interleukin-8 (IL-8) secretion, but lipase- and mutanolysin-treated E. hirae ATCC 9790(T) did not have these effects. It was demonstrated that lipoteichoic acid (LTA) from E. hirae ATCC 9790(T) is responsible for Caco-2 cells' recovery from TNF-alpha-induced impairments. In addition, Caco-2 cells had the same response to Toll-like receptor 2 (TLR2) ligand, Pam(3)Cys-Ser-(Lys)(4) as they did to LTA. Increased expression of zonula occludens-1 was observed by the addition of E. hirae ATCC 9790(T) to TNF-alpha-treated Caco-2 cells, and decreased expression of myosin light chain kinase was observed by the addition of LTA and Pam(3)Cys-Ser-(Lys)(4); this, in turn, led to barrier enforcement. CONCLUSIONS:Enterococcus hirae ATCC 9790(T) cell wall fractions, such as LTA, protect against intestinal impairment by regulation of epithelial tight junction via TLR2 signalling. SIGNIFICANCE AND IMPACT OF THE STUDY: Enterococcus hirae could be useful in the treatment of inflammatory bowel disease, as well as other intestinal disorders.
Authors: S Viaud; R Daillère; I G Boneca; P Lepage; P Langella; M Chamaillard; M J Pittet; F Ghiringhelli; G Trinchieri; R Goldszmid; L Zitvogel Journal: Cell Death Differ Date: 2014-05-16 Impact factor: 15.828
Authors: Mojgan Zadeh; Mohammad W Khan; Yong Jun Goh; Kurt Selle; Jennifer L Owen; Todd Klaenhammer; Mansour Mohamadzadeh Journal: J Inflamm (Lond) Date: 2012-03-16 Impact factor: 4.981
Authors: Lily Nahidi; Steven T Leach; Hazel M Mitchell; Nadeem O Kaakoush; Daniel A Lemberg; John S Munday; Karina Huinao; Andrew S Day Journal: Biomed Res Int Date: 2013-08-06 Impact factor: 3.411