title: Modulation of chemokine gene expression by Shiga-toxin producing Escherichia coli belonging to various origins and serotypes.
abstract: Infection with Shiga-toxin producing Escherichia coli (STEC) may result in the development of the haemolytic-uremic syndrome (HUS), the main cause of acute renal failure in children. While O157:H7 STEC are associated with large outbreaks of HUS, it is difficult to predict whether a non-O157:H7 isolate can be pathogenic for humans. The mucosal innate immune response plays a central role in the pathogenesis of HUS; therefore, we compared the induction of IL-8 and CCL20 in human colon epithelial cells infected with strains belonging to different serotypes, isolated from cattle or from HUS patients. No correlation was observed between strain virulence and chemokine gene expression. Rather, the genetic background of the strains seems to determine the chemokine gene expression profile. Investigating the contribution of different bacterial factors in this process, we show that the type III secretion system of O157:H7 bacteria, but not the intimate adhesion, is required to stimulate the cells. In addition, H7, H10, and H21 flagellins are potent inducers of chemokine gene expression when synthesized in large amount.
authors.affiliation: Institut National de la Recherche Agronomique (INRA), UR454 Unité de Microbiologie, Centre de Theix, 63122 Saint-Genès-Champanelle, France. agobert@clermont.inra.fr
authors.forename: Alain P
authors.initials: AP
authors.lastname: Gobert
authors.forename: Alix
authors.initials: A
authors.lastname: Coste
authors.forename: Carlos A
authors.initials: CA
authors.lastname: Guzman
authors.forename: Marjolaine
authors.initials: M
authors.lastname: Vareille
authors.forename: Thomas
authors.initials: T
authors.lastname: Hindré
authors.forename: Thibaut
authors.initials: T
authors.lastname: de Sablet
authors.forename: Jean-Pierre
authors.initials: JP
authors.lastname: Girardeau
authors.forename: Christine
authors.initials: C
authors.lastname: Martin
mesh_terms: D018829:Adhesins, Bacterial / Q000276:immunology; D000818:Animals; D002417:Cattle; D002418:Cattle Diseases / Q000276:immunology / Q000382:microbiology; D002460:Cell Line; D018925:Chemokines / Q000096:biosynthesis* / Q000235:genetics; D004847:Epithelial Cells / Q000276:immunology / Q000382:microbiology; D004927:Escherichia coli Infections / Q000276:immunology* / Q000662:veterinary; D029968:Escherichia coli Proteins / Q000235:genetics / Q000276:immunology; D005408:Flagellin / Q000276:immunology; D020869:Gene Expression Profiling; D006801:Humans; D026901:Membrane Transport Proteins / Q000276:immunology; D010750:Phosphoproteins / Q000235:genetics; D022622:Shiga Toxin 1 / Q000235:genetics; D022641:Shiga Toxin 2 / Q000235:genetics; D054323:Shiga-Toxigenic Escherichia coli / Q000145:classification* / Q000276:immunology* / Q000302:isolation & purification; D037521:Virulence Factors / Q000235:genetics
chemical_list: D018829:Adhesins, Bacterial; D018925:Chemokines; D029968:Escherichia coli Proteins; C457340:LEE protein, E coli; D026901:Membrane Transport Proteins; D010750:Phosphoproteins; D022622:Shiga Toxin 1; D022641:Shiga Toxin 2; D037521:Virulence Factors; D005408:Flagellin; C073819:eaeA protein, E coli