scholarly journals Development of Heptylmannoside-Based Glycoconjugate Antiadhesive Compounds against Adherent-Invasive Escherichia coli Bacteria Associated with Crohn's Disease

mBio ◽  
2015 ◽  
Vol 6 (6) ◽  
Author(s):  
Adeline Sivignon ◽  
Xibo Yan ◽  
Dimitri Alvarez Dorta ◽  
Richard Bonnet ◽  
Julie Bouckaert ◽  
...  
Keyword(s):  
Escherichia Coli ◽  
Crohn’S Disease ◽  
Crohn's Disease ◽  
Intestinal Inflammation ◽  
Intestinal Epithelial ◽  
Content Type ◽  
Type 1 Pili

ABSTRACTThe ileal lesions of Crohn's disease (CD) patients are colonized by adherent-invasiveEscherichia 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 ofn-heptyl α-d-mannoside (HM), a nanomolar antagonist of FimH, were testedin vitroin IEC infected with the AIEC LF82 strain andin vivoby 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 efficacyin vivoin 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 effectsin 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.IMPORTANCECurrent 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-invasiveEscherichia 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 cellsin vitro. The antiadhesive effect of two of these compounds of relatively simple chemical structure was also observedin vivoin 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.

scholarly journals The Oxidoreductase DsbA Plays a Key Role in the Ability of the Crohn's Disease-Associated Adherent-Invasive Escherichia coli Strain LF82 To Resist Macrophage Killing

2007 ◽  
Vol 189 (13) ◽  
pp. 4860-4871 ◽  
Author(s):  
Marie-Agnès Bringer ◽  
Nathalie Rolhion ◽  
Anne-Lise Glasser ◽  
Arlette Darfeuille-Michaud
Keyword(s):  
Escherichia Coli ◽  
Crohn’S Disease ◽  
Crohn's Disease ◽  
Epithelial Cells ◽  
Intestinal Epithelial Cells ◽  
Coli Strain ◽  
Intestinal Epithelial ◽  
Type 1 Pili ◽  
K 12

ABSTRACT Adherent-invasive Escherichia coli (AIEC) isolated from Crohn's disease patients is able to adhere to and invade intestinal epithelial cells and to replicate in mature phagolysosomes within macrophages. Here, we show that the dsbA gene, encoding a periplasmic oxidoreductase, was required for AIEC strain LF82 to adhere to intestinal epithelial cells and to survive within macrophages. The LF82-ΔdsbA mutant did not express flagella and, probably as a consequence of this, did not express type 1 pili. The role of DsbA in adhesion is restricted to the loss of flagella and type 1 pili, as forced contact between bacteria and cells and induced expression of type 1 pili restored the wild-type phenotype. In contrast, the dsbA gene is essential for AIEC LF82 bacteria to survive within macrophages, irrespective of the loss of flagella and type 1 pilus expression, and the survival ability of LF82-ΔdsbA was as low as that of the nonpathogenic E. coli K-12, which was efficiently killed by macrophages. We also provide evidence that the dsbA gene is needed for LF82 bacteria to grow and survive in an acidic and nutrient-poor medium that partly mimics the harsh environment of the phagocytic vacuole. In addition, under such stress conditions dsbA transcription is highly up-regulated. Finally, the CpxRA signaling pathway does not play a role in regulation of dsbA expression in AIEC LF82 bacteria under conditions similar to those of mature phagolysosomes.

scholarly journals Role of Decreased Levels of Fis Histone-Like Protein in Crohn's Disease-Associated Adherent Invasive Escherichia coli LF82 Bacteria Interacting with Intestinal Epithelial Cells

2010 ◽  
Vol 192 (7) ◽  
pp. 1832-1843 ◽  
Author(s):  
Sylvie Miquel ◽  
Laurent Claret ◽  
Richard Bonnet ◽  
Imen Dorboz ◽  
Nicolas Barnich ◽  
...  
Keyword(s):  
Escherichia Coli ◽  
Crohn’S Disease ◽  
Crohn's Disease ◽  
Epithelial Cells ◽  
Intestinal Epithelial Cells ◽  
Host Cells ◽  
Intestinal Epithelial ◽  
Type 1 Pili

ABSTRACT The interaction of Crohn's disease (CD)-associated adherent-invasive Escherichia coli (AIEC) strain LF82 with intestinal epithelial cells depends on surface appendages, such as type 1 pili and flagella. Histone-like proteins operate as global regulators to control the expression of these virulence factors. We evaluated the role of histone-like proteins in AIEC reference strain LF82 during infection of intestinal epithelial cells, Intestine-407, and observed that the fis mRNA level was decreased. The role of Fis in AIEC LF82 was determined by studying the phenotype of an LF82 fis::Km mutant. This was the first mutant of strain LF82 that has been described thus far that is unable to express flagellin but still able to produce type 1 pili. The cyclic-di-GMP pathway linking flagella and type 1 pilus expression is not involved in Fis-mediated regulation, and we identified in the present study Fis-binding sites located upstream of the fimE gene and in the intergenic region between fimB and nanC of the fim operon encoding type 1 pili. The major consequence of decreased Fis expression in AIEC bacteria in contact with host cells is a direct downregulation of fimE expression, leading to the preferential ON phase of the fimS element. Thus, by maintaining type 1 pilus expression, AIEC bacteria, which interact with the gut mucosa, have greater ability to colonize and to induce inflammation in CD patients.

scholarly journals Involvement of Lipoprotein NlpI in the Virulence of Adherent Invasive Escherichia coli Strain LF82 Isolated from a Patient with Crohn's Disease

2004 ◽  
Vol 72 (5) ◽  
pp. 2484-2493 ◽  
Author(s):  
Nicolas Barnich ◽  
Marie-Agnès Bringer ◽  
Laurent Claret ◽  
Arlette Darfeuille-Michaud
Keyword(s):  
Escherichia Coli ◽  
Crohn’S Disease ◽  
Crohn's Disease ◽  
Epithelial Cells ◽  
Intestinal Epithelial Cells ◽  
Mrna Level ◽  
Mrna Levels ◽  
Intestinal Epithelial ◽  
Type 1 Pili

ABSTRACT Escherichia coli strain LF82 recovered from a chronic lesion of a patient with Crohn's disease (CD) is able to adhere to and invade cultured intestinal epithelial cells and to replicate within macrophages. One mutant selected for its impaired ability to invade epithelial cells had an insertion of a Tn phoA transposon within the nlpI gene encoding the lipoprotein NlpI. A NlpI-negative isogenic mutant showed a 35-fold decrease in its ability to adhere to and a 45-fold decrease in its ability to invade Intestine-407 cells, but its ability to survive and to replicate within macrophages was similar to that of wild-type strain LF82. In addition, this mutant did not express flagella and synthesized very small amounts of type 1 pili. Downregulation of type 1 pili in the NlpI-negative mutant resulted from a preferential switch toward the OFF position of the invertible DNA element located upstream of the fim operon. The FimB and FimE recombinases act in concert to control the switch, and a large decrease in fimB and fimE mRNA levels was observed. The absence of flagellar structures correlated with a drastic 19-fold decrease in the fliC mRNA level, regardless of the FlhD2C2 transcriptional regulator and of the σ28 transcription factor. The key role of NlpI in virulence is independent of type 1 pili and motility, since induced type 1 pilus expression and/or forced contact between bacteria and intestinal epithelial cells did not restore the ability of the NlpI mutant to adhere to and to invade intestinal epithelial cells.

scholarly journals Prolonged NF-κB Activation by a Macrophage Inhibitory Cytokine 1-Linked Signal in Enteropathogenic Escherichia coli-Infected Epithelial Cells

2013 ◽  
Vol 81 (6) ◽  
pp. 1860-1869 ◽  
Author(s):  
Hye Jin Choi ◽  
Juil Kim ◽  
Kee Hun Do ◽  
Seong-Hwan Park ◽  
Yuseok Moon
Keyword(s):  
Escherichia Coli ◽  
Epithelial Cells ◽  
Transforming Growth Factor ◽  
Watery Diarrhea ◽  
Intestinal Epithelial ◽  
Severe Injuries ◽  
Epithelial Integrity ◽  
Content Type

ABSTRACTIntestinal epithelial activation of nuclear factor kappa B (NF-κB) exerts both detrimental and beneficial functions in response to various luminal insults, including ones associated with mucosa-associated pathogens. Gastrointestinal infection with enteropathogenicEscherichia coli(EPEC) causes severe injuries in epithelial integrity and leads to watery diarrhea. The present study was conducted to investigate the prolonged epithelial responses to persistent EPEC infection via NF-κB activation. EPEC infection led to sustained activation of NF-κB signal in mouse intestinal epithelial cellsin vivoandin vitro, which was positively associated with a type III secretion system, whereas early NF-κB is regulated. Moreover, prolonged NF-κB activation was found to be a part of macrophage inhibitory cytokine 1 (MIC-1)-mediated signaling activation, a novel link between NF-κB signaling and infection-associated epithelial stress. EPEC infection induced gene expression of MIC-1, a member of the transforming growth factor β (TGF-β) superfamily, which then activated TGF-β-activated kinase 1 and consequently led to NF-κB activation. Functionally, both EPEC-induced MIC-1 and NF-κB signaling mediated epithelial survival by enhancing the expression of cyclin D1, a target of NF-κB. In summary, the results of the present study suggest that MIC-1 serves as a mediator of prolonged NF-κB activation, which is critical in maintaining gut epithelial integrity in response to infection-induced injuries.

scholarly journals Analysis of the σERegulon in Crohn's Disease-Associated Escherichia coli Revealed Involvement of thewaaWVLOperon in Biofilm Formation

2015 ◽  
Vol 197 (8) ◽  
pp. 1451-1465 ◽  
Author(s):  
Benoit Chassaing ◽  
Estelle Garénaux ◽  
Jessica Carriere ◽  
Nathalie Rolhion ◽  
Yann Guérardel ◽  
...  
Keyword(s):  
Escherichia Coli ◽  
Crohn’S Disease ◽  
Crohn's Disease ◽  
Intestinal Mucosa ◽  
Biofilm Formation ◽  
Intestinal Epithelial ◽  
Content Type ◽  
E Coli ◽  
Gut Mucosa ◽  
Pathway Inhibition

ABSTRACTIleal lesions of patients with Crohn's disease are colonized by adherent-invasiveEscherichia coli(AIEC), which is able to adhere to and to invade intestinal epithelial cells (IEC), to replicate within macrophages, and to form biofilms on the surface of the intestinal mucosa. Previous analyses indicated the involvement of the σEpathway in AIEC-IEC interaction, as well as in biofilm formation, with σEpathway inhibition leading to an impaired ability of AIEC to colonize the intestinal mucosa and to form biofilms. The aim of this study was to characterize the σEregulon of AIEC strain LF82 in order to identify members involved in AIEC phenotypes. Using comparativein silicoanalysis of the σEregulon, we identified thewaaWVLoperon as a new member of the σEregulon in reference AIEC strain LF82. We determined that thewaaWVLoperon is involved in AIEC lipopolysaccharide structure and composition, and thewaaWVLoperon was found to be essential for AIEC strains to produce biofilm and to colonize the intestinal mucosa.IMPORTANCEAn increased prevalence of adherent-invasiveEscherichia coli(AIEC) bacteria was previously observed in the intestinal mucosa of Crohn's disease (CD) patients, and clinical observations revealed bacterial biofilms associated with the mucosa of CD patients. Here, analysis of the σEregulon in AIEC and commensalE. coliidentified 12 genes controlled by σEonly in AIEC. Among them, WaaWVL factors were found to play an essential role in biofilm formation and mucosal colonization by AIEC. In addition to identifying molecular tools that revealed a pathogenic population ofE. colicolonizing the mucosa of CD patients, these results indicate that targeting thewaaWVLoperon could be a potent therapeutic strategy to interfere with the ability of AIEC to form biofilms and to colonize the gut mucosa.

scholarly journals Intestinal Epithelial CD98 Directly Modulates the Innate Host Response to Enteric Bacterial Pathogens

2013 ◽  
Vol 81 (3) ◽  
pp. 923-934 ◽  
Author(s):  
Moiz A. Charania ◽  
Hamed Laroui ◽  
Hongchun Liu ◽  
Emilie Viennois ◽  
Saravanan Ayyadurai ◽  
...  
Keyword(s):  
Intestinal Inflammation ◽  
Ex Vivo ◽  
Host Cells ◽  
Intestinal Epithelial ◽  
Extracellular Loop ◽  
Ki 67 ◽  
Content Type ◽  
Direct Binding

ABSTRACTCD98 is a type II transmembrane glycoprotein whose expression increases in intestinal epithelial cells (IECs) during intestinal inflammation. EnteropathogenicEscherichia coli(EPEC) is a food-borne human pathogen that attaches to IECs and injects effector proteins directly into the host cells, thus provoking an inflammatory response. In the present study, we investigated CD98 and EPEC interactionsin vitroandex vivoand examined FVB wild-type (WT) and villin-CD98 transgenic mice overexpressing human CD98 in IECs (hCD98 Tg mice) and infected withCitrobacter rodentiumas anin vivomodel.In vivostudies indicated that CD98 overexpression, localized to the apical domain of colonic cells, increased the attachment ofC. rodentiumin mouse colons and resulted in increased expression of proinflammatory markers and decreased expression of anti-inflammatory markers. The proliferative markers Ki-67 and cyclin D1 were significantly increased in the colonic tissue ofC. rodentium-infected hCD98 Tg mice compared to that of WT mice.Ex vivostudies correlate with thein vivodata. Small interfering RNA (siRNA) studies with Caco2-BBE cells showed a decrease in adherence of EPEC to Caco2 cells in which CD98 expression was knocked down.In vitrosurface plasmon resonance (SPR) experiments showed direct binding between recombinant hCD98 and EPEC/C. rodentiumproteins. We also demonstrated that the partial extracellular loop of hCD98 was sufficient for direct binding to EPEC/C. rodentium. These findings demonstrate the importance of the extracellular loop of CD98 in the innate host defense response to intestinal infection by attaching and effacing (A/E) pathogens.

Establishing the phenotypic basis of adherent-invasive Escherichia coli (AIEC) pathogenicity in intestinal inflammation

2019 ◽  
Author(s):  
Hatem Kittana ◽  
João C. Gomes-Neto ◽  
Kari Heck ◽  
Jason Sughroue ◽  
Yibo Xian ◽  
...  
Keyword(s):  
Escherichia Coli ◽  
Intestinal Inflammation ◽  
Intestinal Epithelial ◽  
Disease Etiology ◽  
E Coli ◽  
Caco2 Cells ◽  
Phenotypic Group ◽  
Tnf Α

AbstractBackground & AimsAdherent-invasive Escherichia coli (AIEC) are enriched in ileal Crohn’s disease patients and implicated in disease etiology. However, AIEC pathogenesis is poorly understood, and it is unclear if the expansion of these organisms contributes to inflammatory bowel disease (IBD). Questions also remain as to what extent the various in vitro phenotypes used to classify AIEC are pathologically relevant.MethodsWe utilized a combination of in vitro phenotyping and a murine model of intestinal inflammation to systematically relate AIEC phenotypes to pathogenicity for 30 mucosa-associated human-derived E. coli strains. In vitro assays used included survival/replication in and TNF-α production by J774 macrophages as well as invasion/replication in Caco2 intestinal epithelial cells.ResultsAIEC do not form a phenotypic group that is clearly separated from non-AIEC. However, E. coli strains displaying in vitro AIEC phenotypes caused, on average, more severe intestinal inflammation. Survival/replication of strains in J774 and Caco2 cells were positively correlated with disease in vivo, while adherence to Caco2 cells and TNF-α production by J774 cells were not. Importantly, co-colonization with adherent non-AIEC strains ameliorated AIEC-mediated disease.ConclusionOur findings do not support the existence of an AIEC pathovar that can be clearly separated from commensal E. coli. However, intracellular survival/replication phenotypes do contribute to murine intestinal inflammation, suggesting that the AIEC overgrowth observed in human IBD makes a causal contribution to disease. The ability to differentiate pathologically-relevant AIEC phenotypes from those that are not provides an important foundation for developing strategies to predict, diagnose and treat human IBD through characterizing and modulating patient E. coli populations.

scholarly journals Crohn's disease adherent-invasive Escherichia coli colonize and induce strong gut inflammation in transgenic mice expressing human CEACAM

2009 ◽  
Vol 206 (10) ◽  
pp. 2179-2189 ◽  
Author(s):  
Frédéric A. Carvalho ◽  
Nicolas Barnich ◽  
Adeline Sivignon ◽  
Claude Darcha ◽  
Carlos H.F. Chan ◽  
...  
Keyword(s):  
Escherichia Coli ◽  
Crohn’S Disease ◽  
Crohn's Disease ◽  
Transgenic Mice ◽  
Intestinal Mucosa ◽  
Apical Surface ◽  
Gut Inflammation ◽  
Type 1 Pili ◽  
K 12

Abnormal expression of CEACAM6 is observed at the apical surface of the ileal epithelium in Crohn's disease (CD) patients, and CD ileal lesions are colonized by pathogenic adherent-invasive Escherichia coli (AIEC). We investigated the ability of AIEC reference strain LF82 to colonize the intestinal mucosa and to induce inflammation in CEABAC10 transgenic mice expressing human CEACAMs. AIEC LF82 virulent bacteria, but not nonpathogenic E. coli K-12, were able to persist in the gut of CEABAC10 transgenic mice and to induce severe colitis with reduced survival rate, marked weight loss, increased rectal bleeding, presence of erosive lesions, mucosal inflammation, and increased proinflammatory cytokine expression. The colitis depended on type 1 pili expression by AIEC bacteria and on intestinal CEACAM expression because no sign of colitis was observed in transgenic mice infected with type 1 pili–negative LF82-ΔfimH isogenic mutant or in wild-type mice infected with AIEC LF82 bacteria. These findings strongly support the hypothesis that in CD patients having an abnormal intestinal expression of CEACAM6, AIEC bacteria via type 1 pili expression can colonize the intestinal mucosa and induce gut inflammation. Thus, targeting AIEC adhesion to gut mucosa represents a new strategy for clinicians to prevent and/or to treat ileal CD.

scholarly journals Creatine Supplementation for Patients with Inflammatory Bowl Diseases: A Scientific Rationale for a Clinical Trial

Nutrients ◽  
2021 ◽  
Vol 13 (5) ◽  
pp. 1429
Author(s):  
Theo Wallimann ◽  
Caroline H. T. Hall ◽  
Sean P. Colgan ◽  
Louise E. Glover
Keyword(s):  
Ulcerative Colitis ◽  
Clinical Trial ◽  
Crohn’S Disease ◽  
Pilot Study ◽  
Crohn's Disease ◽  
Single Case ◽  
Initial Period ◽  
Creatine Supplementation

Based on theoretical considerations, experimental data with cells in vitro, animal studies in vivo, as well as a single case pilot study with one colitis patient, a consolidated hypothesis can be put forward, stating that “oral supplementation with creatine monohydrate (Cr), a pleiotropic cellular energy precursor, is likely to be effective in inducing a favorable response and/or remission in patients with inflammatory bowel diseases (IBD), like ulcerative colitis and/or Crohn’s disease”. A current pilot clinical trial that incorporates the use of oral Cr at a dose of 2 × 7 g per day, over an initial period of 2 months in conjunction with ongoing therapies (NCT02463305) will be informative for the proposed larger, more long-term Cr supplementation study of 2 × 3–5 g of Cr per day for a time of 3–6 months. This strategy should be insightful to the potential for Cr in reducing or alleviating the symptoms of IBD. Supplementation with chemically pure Cr, a natural nutritional supplement, is well tolerated not only by healthy subjects, but also by patients with diverse neuromuscular diseases. If the outcome of such a clinical pilot study with Cr as monotherapy or in conjunction with metformin were positive, oral Cr supplementation could then be used in the future as potentially useful adjuvant therapeutic intervention for patients with IBD, preferably together with standard medication used for treating patients with chronic ulcerative colitis and/or Crohn’s disease.

Sign in / Sign up

Export Citation Format

Share Document