The ex vivo response of human intestinal mucosa to enteropathogenic Escherichia coli infection

In vitro organ culture (IVOC) represents a gold standard model to study enteropathogenic E. coli (EPEC) infection of human intestinal mucosa. However, the optimal examination of the bacterial–host cell interaction requires a directional epithelial exposure, without serosal or cut surface stimulation. A polarized IVOC system (pIVOC) was developed in order to overcome such limitations: apical EPEC infection produced negligible bacterial leakage via biopsy edges, resulted in enhanced colonization compared with standard IVOC, and showed evidence of bacterial detachment, as in natural rabbit EPEC infections. Examination of mucosal innate immune responses in pIVOC showed both interleukin (IL)‐8 mRNA and protein levels were significantly increased after apical EPEC infection. Increased IL‐8 levels mainly depended on flagellin expression as fliC‐negative EPEC did not elicit a significant IL‐8 response despite increased mucosal colonization compared with wild‐type EPEC. In addition, apical application of purified flagella significantly increased IL‐8 protein levels over non‐infected controls. Immunofluorescence staining of EPEC‐infected small intestinal biopsies revealed apical and basolateral distribution of Toll‐like receptor (TLR) 5 on epithelium, suggesting that EPEC can trigger mucosal IL‐8 responses by apical flagellin/TLR5 interaction ex vivo and does not require access to the basolateral membrane as postulated in cell culture models.

[1]  C. Rosenberger,et al.  Flagellin-Dependent and -Independent Inflammatory Responses following Infection by Enteropathogenic Escherichia coli and Citrobacter rodentium , 2008, Infection and Immunity.

[2]  J. Kaper,et al.  Enteropathogenic Escherichia coli O125:H6 Triggers Attaching and Effacing Lesions on Human Intestinal Biopsy Specimens Independently of Nck and TccP/TccP2 , 2007, Infection and Immunity.

[3]  J. Xicohtencatl-Cortes,et al.  Host Protein Binding and Adhesive Properties of H6 and H7 Flagella of Attaching and Effacing Escherichia coli , 2007, Journal of bacteriology.

[4]  B. Kenny,et al.  Enteropathogenic Escherichia coli (EPEC) inactivate innate immune responses prior to compromising epithelial barrier function , 2007, Cellular microbiology.

[5]  B. Kenny,et al.  Tir phosphorylation and Nck/N‐WASP recruitment by enteropathogenic and enterohaemorrhagic Escherichia coli during ex vivo colonization of human intestinal mucosa is different to cell culture models , 2007, Cellular microbiology.

[6]  M. Kagnoff,et al.  Role of Shiga toxin versus H7 flagellin in enterohaemorrhagic Escherichia coli signalling of human colon epithelium in vivo , 2006, Cellular microbiology.

[7]  Rachna Sharma,et al.  Balance of bacterial pro- and anti-inflammatory mediators dictates net effect of enteropathogenic Escherichia coli on intestinal epithelial cells. , 2006, American journal of physiology. Gastrointestinal and liver physiology.

[8]  C. Pothoulakis,et al.  Pathophysiological role of Toll-like receptor 5 engagement by bacterial flagellin in colonic inflammation. , 2005, Proceedings of the National Academy of Sciences of the United States of America.

[9]  S. Rubino,et al.  The Vi Capsular Antigen of Salmonella enterica Serotype Typhi Reduces Toll-Like Receptor-Dependent Interleukin-8 Expression in the Intestinal Mucosa , 2005, Infection and Immunity.

[10]  F. Taddei,et al.  In Vitro and ex Vivo Activation of the TLR5 Signaling Pathway in Intestinal Epithelial Cells by a Commensal Escherichia coli Strain* , 2004, Journal of Biological Chemistry.

[11]  H. Müller-Hermelink,et al.  Expression and subcellular distribution of toll‐like receptors TLR4, TLR5 and TLR9 on the gastric epithelium in Helicobacter pylori infection , 2004, Clinical and experimental immunology.

[12]  D. Binion,et al.  Human Intestinal Microvascular Endothelial Cells Express Toll-Like Receptor 5: A Binding Partner for Bacterial Flagellin , 2004, The Journal of Immunology.

[13]  G. Frankel,et al.  Interaction of Shiga toxin from Escherichia coli with human intestinal epithelial cell lines and explants: Stx2 induces epithelial damage in organ culture , 2004, Cellular microbiology.

[14]  M. Donnenberg,et al.  Enteropathogenic Escherichia coli (EPEC) adhesion to intestinal epithelial cells: role of bundle-forming pili (BFP), EspA filaments and intimin. , 2004, Microbiology.

[15]  K. Rottner,et al.  Enterohaemorrhagic and enteropathogenic Escherichia coli use different mechanisms for actin pedestal formation that converge on N‐WASP , 2004, Cellular microbiology.

[16]  D. Merlin,et al.  TLR5-mediated activation of p38 MAPK regulates epithelial IL-8 expression via posttranscriptional mechanism , 2003 .

[17]  A. Torres,et al.  Flagellin of Enteropathogenic Escherichia coli Stimulates Interleukin-8 Production in T84 Cells , 2003, Infection and Immunity.

[18]  D. Merlin,et al.  TLR5-mediated activation of p38 MAPK regulates epithelial IL-8 expression via posttranscriptional mechanism. , 2003, American journal of physiology. Gastrointestinal and liver physiology.

[19]  G. Coppa,et al.  Host-dependent zonulin secretion causes the impairment of the small intestine barrier function after bacterial exposure. , 2002, Gastroenterology.

[20]  M. Kagnoff,et al.  Role of EHEC O157:H7 virulence factors in the activation of intestinal epithelial cell NF‐κB and MAP kinase pathways and the upregulated expression of interleukin 8 , 2002, Cellular microbiology.

[21]  A. Torres,et al.  The flagella of enteropathogenic Escherichia coli mediate adherence to epithelial cells , 2002, Molecular microbiology.

[22]  T. Pawson,et al.  Enteropathogenic E. coli Tir binds Nck to initiate actin pedestal formation in host cells , 2001, Nature Cell Biology.

[23]  P. Godowski,et al.  Cutting Edge: Bacterial Flagellin Activates Basolaterally Expressed TLR5 to Induce Epithelial Proinflammatory Gene Expression1 , 2001, The Journal of Immunology.

[24]  B. Finlay,et al.  Decreased Apoptosis in the Ileum and Ileal Peyer's Patches: a Feature after Infection with Rabbit EnteropathogenicEscherichia coli O103 , 2001, Infection and Immunity.

[25]  S. Akira,et al.  The innate immune response to bacterial flagellin is mediated by Toll-like receptor 5 , 2001, Nature.

[26]  D. Podolsky,et al.  Differential Alteration in Intestinal Epithelial Cell Expression of Toll-Like Receptor 3 (TLR3) and TLR4 in Inflammatory Bowel Disease , 2000, Infection and Immunity.

[27]  B. Wanner,et al.  One-step inactivation of chromosomal genes in Escherichia coli K-12 using PCR products. , 2000, Proceedings of the National Academy of Sciences of the United States of America.

[28]  B. Kenny.  Phosphorylation of tyrosine 474 of the enteropathogenic Escherichia coli (EPEC) Tir receptor molecule is essential for actin nucleating activity and is preceded by additional host modifications , 1999, Molecular microbiology.

[29]  S. Hicks,et al.  Adhesion of enteroaggregative Escherichia coli to pediatric intestinal mucosa in vitro , 1996, Infection and immunity.

[30]  S. Savkovic,et al.  Attachment of a noninvasive enteric pathogen, enteropathogenic Escherichia coli, to cultured human intestinal epithelial monolayers induces transmigration of neutrophils , 1996, Infection and immunity.

[31]  D. Philpott,et al.  Infection of T84 cells with enteropathogenic Escherichia coli alters barrier and transport functions. , 1996, The American journal of physiology.

[32]  J. Alverdy,et al.  Enteropathogenic Escherichia coli adherence to intestinal epithelial monolayers diminishes barrier function. , 1995, The American journal of physiology.

[33]  J. Yu,et al.  A genetic locus of enteropathogenic Escherichia coli necessary for the production of attaching and effacing lesions on tissue culture cells. , 1990, Proceedings of the National Academy of Sciences of the United States of America.

[34]  P. Williams,et al.  Actin accumulation at sites of bacterial adhesion to tissue culture cells: basis of a new diagnostic test for enteropathogenic and enterohemorrhagic Escherichia coli , 1989, Infection and immunity.

[35]  Phillips Ad,et al.  Polymorphonuclear Neutrophil Leucocytes in Childhood Crohn's Disease: A Morphological Study , 1987, Journal of pediatric gastroenterology and nutrition.

[36]  S. Knutton,et al.  Adhesion of enteropathogenic Escherichia coli to human intestinal enterocytes and cultured human intestinal mucosa , 1987, Infection and immunity.

[37]  M. Levine,et al.  The diarrheal response of humans to some classic serotypes of enteropathogenic Escherichia coli is dependent on a plasmid encoding an enteroadhesiveness factor. , 1985, The Journal of infectious diseases.

[38]  M. Levine,et al.  Attaching and effacing activities of rabbit and human enteropathogenic Escherichia coli in pig and rabbit intestines , 1983, Infection and immunity.

[39]  A. J. Mcadams,et al.  An ultrastructural study of enteropathogenic Escherichia coli infection in human infants. , 1983, Ultrastructural pathology.

[40]  M. Ulshen,et al.  Pathogenesis of escherichia coli gastroenteritis in man--another mechanism. , 1980, The New England journal of medicine.

[41]  G. Frankel,et al.  Enteropathogenic Escherichia coli: unravelling pathogenesis. , 2005, FEMS microbiology reviews.

[42]  S. Targan,et al.  Bacterial flagellin is a dominant antigen in Crohn disease. , 2004, The Journal of clinical investigation.

[43]  A. Aderem,et al.  The Toll-Like Receptor 5 Stimulus Bacterial Flagellin Induces Maturation and Chemokine Production in Human Dendritic Cells , 2003 .