title: Development of Heptylmannoside-Based Glycoconjugate Antiadhesive Compounds against Adherent-Invasive Escherichia coli Bacteria Associated with Crohn's Disease.
abstract: The ileal lesions of Crohn's disease (CD) patients are colonized by adherent-invasive Escherichia coli (AIEC) bacteria. These bacteria adhere to mannose residues expressed by CEACAM6 on host cells in a type 1 pilus-dependent manner. In this study, we investigated different antagonists of FimH, the adhesin of type 1 pili, for their ability to block AIEC adhesion to intestinal epithelial cells (IEC). Monovalent and multivalent derivatives of n-heptyl α-d-mannoside (HM), a nanomolar antagonist of FimH, were tested in vitro in IEC infected with the AIEC LF82 strain and in vivo by oral administration to CEACAM6-expressing mice infected with LF82 bacteria. In vitro, multivalent derivatives were more potent than the monovalent derivatives, with a gain of efficacy superior to their valencies, probably owing to their ability to form bacterial aggregates. Of note, HM and the multi-HM glycoconjugates exhibited lower efficacy in vivo in decreasing LF82 gut colonization. Interestingly, HM analogues functionalized with an isopropylamide (1A-HM) or β-cyclodextrin pharmacophore at the end of the heptyl tail (1CD-HM) exerted beneficial effects in vivo. These two compounds strongly decreased the amount of LF82 bacteria in the feces of mice and that of bacteria associated with the gut mucosa when administered orally at a dose of 10 mg/kg of body weight after infection. Importantly, signs of colitis and intestinal inflammation induced by LF82 infection were also prevented. These results highlight the potential of the antiadhesive compounds to treat CD patients abnormally colonized by AIEC bacteria and point to an alternative to the current approach focusing on blocking proinflammatory mediators.
  
  
  OBJECTIVE
  Current treatments for Crohn's disease (CD), including immunosuppressive agents, anti-tumor necrosis factor alpha (anti-TNF-α) and anti-integrin antibodies, focus on the symptoms but not on the cause of the disease. Adherent-invasive Escherichia coli (AIEC) bacteria abnormally colonize the ileal mucosa of CD patients via the interaction of the mannose-specific adhesin FimH of type 1 pili with CEACAM6 mannosylated proteins expressed on the epithelial cell surface. Thus, we decided to develop an antiadhesive strategy based on synthetic FimH antagonists specifically targeting AIEC bacteria that would decrease intestinal inflammation. Heptylmannoside (HM)-based glycocompounds strongly inhibit AIEC adhesion to intestinal epithelial cells in vitro. The antiadhesive effect of two of these compounds of relatively simple chemical structure was also observed in vivo in AIEC-infected CEACAM6-expressing mice and was associated with a reduction in the signs of colitis. These results suggest a new therapeutic approach for CD patients colonized by AIEC bacteria, based on the development of synthetic FimH antagonists.
authors.affiliation: Clermont Université, UMR 1071 INSERM/Université d'Auvergne, Clermont-Ferrand, France INRA, Unité Sous Contrat 2018, Clermont-Ferrand, France.
authors.forename: Adeline
authors.initials: A
authors.lastname: Sivignon
authors.affiliation: Université de Lyon, Lyon, France INSA-Lyon, Ingénierie des Matériaux Polymères (IMP), Villeurbanne, France CNRS, UMR 5223, Ingénierie des Matériaux Polymères, Villeurbanne, France.
authors.forename: Xibo
authors.initials: X
authors.lastname: Yan
authors.affiliation: LUNAM Université, Chimie et Interdisciplinarité, Synthèse, Analyse, Modélisation (CEISAM), UMR CNRS 6230, UFR des Sciences et des Techniques, Nantes, France.
authors.forename: Dimitri
authors.initials: D
authors.lastname: Alvarez Dorta
authors.affiliation: Clermont Université, UMR 1071 INSERM/Université d'Auvergne, Clermont-Ferrand, France INRA, Unité Sous Contrat 2018, Clermont-Ferrand, France Centre Hospitalier Universitaire, Clermont-Ferrand, France.
authors.forename: Richard
authors.initials: R
authors.lastname: Bonnet
authors.affiliation: Unité de Glycobiologie Structurale et Fonctionnelle (UGSF), UMR8576, CNRS, Université Lille 1, Lille, France.
authors.forename: Julie
authors.initials: J
authors.lastname: Bouckaert
authors.affiliation: Université de Lyon, Lyon, France INSA-Lyon, Ingénierie des Matériaux Polymères (IMP), Villeurbanne, France CNRS, UMR 5223, Ingénierie des Matériaux Polymères, Villeurbanne, France.
authors.forename: Etienne
authors.initials: E
authors.lastname: Fleury
authors.affiliation: Université de Lyon, Lyon, France INSA-Lyon, Ingénierie des Matériaux Polymères (IMP), Villeurbanne, France CNRS, UMR 5223, Ingénierie des Matériaux Polymères, Villeurbanne, France.
authors.forename: Julien
authors.initials: J
authors.lastname: Bernard
authors.affiliation: LUNAM Université, Chimie et Interdisciplinarité, Synthèse, Analyse, Modélisation (CEISAM), UMR CNRS 6230, UFR des Sciences et des Techniques, Nantes, France.
authors.forename: Sébastien G
authors.initials: SG
authors.lastname: Gouin
authors.affiliation: Clermont Université, UMR 1071 INSERM/Université d'Auvergne, Clermont-Ferrand, France INRA, Unité Sous Contrat 2018, Clermont-Ferrand, France.
authors.forename: Arlette
authors.initials: A
authors.lastname: Darfeuille-Michaud
authors.affiliation: Clermont Université, UMR 1071 INSERM/Université d'Auvergne, Clermont-Ferrand, France INRA, Unité Sous Contrat 2018, Clermont-Ferrand, France nicolas.barnich@udamail.fr.
authors.forename: Nicolas
authors.initials: N
authors.lastname: Barnich
mesh_terms: D018830:Adhesins, Escherichia coli; D000284:Administration, Oral; D000818:Animals; D015703:Antigens, CD / Q000235:genetics / Q000378:metabolism; D001422:Bacterial Adhesion / Q000187:drug effects*; D058491:Bacterial Load; D015815:Cell Adhesion Molecules / Q000235:genetics / Q000378:metabolism; D003424:Crohn Disease / Q000382:microbiology*; D055808:Drug Discovery; D004847:Epithelial Cells / Q000187:drug effects / Q000382:microbiology; D004926:Escherichia coli / Q000187:drug effects* / Q000254:growth & development / Q000502:physiology; D004927:Escherichia coli Infections / Q000188:drug therapy* / Q000382:microbiology; D005243:Feces / Q000382:microbiology; D036781:Fimbriae Proteins / Q000037:antagonists & inhibitors; D010861:Fimbriae, Bacterial / Q000378:metabolism; D058851:GPI-Linked Proteins / Q000235:genetics / Q000378:metabolism; D006001:Glycoconjugates / Q000737:chemistry / Q000627:therapeutic use*; D007413:Intestinal Mucosa / Q000187:drug effects / Q000378:metabolism / Q000382:microbiology; D007422:Intestines / Q000166:cytology / Q000382:microbiology; D008362:Mannosides / Q000138:chemical synthesis / Q000737:chemistry / Q000494:pharmacology / Q000627:therapeutic use*; D051379:Mice; D047392:beta-Cyclodextrins
chemical_list: D018830:Adhesins, Escherichia coli; D015703:Antigens, CD; D015815:Cell Adhesion Molecules; D058851:GPI-Linked Proteins; D006001:Glycoconjugates; C575659:Gm5893 protein, mouse; D008362:Mannosides; D047392:beta-Cyclodextrins; C058769:fimH protein, E coli; D036781:Fimbriae Proteins; C031215:betadex