Invasive Ability of an Escherichia coliStrain Isolated from the Ileal Mucosa of a Patient with Crohn’s Disease

ABSTRACT Crohn’s disease (CD) is an inflammatory bowel disease in whichEscherichia coli strains have been suspected of being involved. We demonstrated previously that ileal lesions of CD are colonized by E. coli strains able to adhere to intestinal Caco-2 cells but devoid of the virulence genes so far described in the pathogenic E. coli strains involved in gastrointestinal infections. In the present study we compared the invasive ability of one of these strains isolated from an ileal biopsy of a patient with CD, strain LF82, with that of reference enteroinvasive (EIEC), enteropathogenic (EPEC), enterotoxigenic (ETEC), enteraggregative (EAggEC), enterohemorrhagic (EHEC), and diffusely adhering (DAEC)E. coli strains. Gentamicin protection assays showed thatE. coli LF82 was able to efficiently invade HEp-2 cells. Its invasive level was not significantly different from that of EIEC and EPEC strains (P > 0.5) but significantly higher than that of ETEC (P < 0.03), EHEC (P < 0.005), EAggEC (P < 0.004) and DAEC (P < 0.02) strains. Strain LF82 also demonstrated efficient ability to invade intestinal epithelial cultured Caco-2, Intestine-407, and HCT-8 cells. Electron microscopy examination of infected HEp-2 cells revealed the presence of numerous intracellular bacteria located in vacuoles or free in the host cell cytoplasm. In addition, the interaction of strain LF82 with epithelial cells was associated with the elongation of microvillar extensions that extruded from the host cell membranes and engulfed the bacteria. This internalization mechanism strongly resembles Salmonella- orShigella-induced macropinocytosis. The use of cytochalasin D and colchicine showed that the uptake of strain LF82 by HEp-2 cells was mediated by both an actin microfilament-dependent mechanism and microtubule involvement. In addition, strain LF82 survived for at least 24 h in HEp-2 and Intestine-407 cells and efficiently replicated intracellularly in HEp-2 cells. PCR and hybridization experiments did not reveal the presence of any of the genetic determinants encoding EIEC, EPEC, or ETEC proteins involved in bacterial invasion. Thus, these findings show that LF82, which colonized the ileal mucosa of a patient with CD, is a true invasive E. coli strain and suggest the existence of a new potentially pathogenic group of E. coli, which we propose be designated adherent-invasive E. coli.

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DOP06 Non-invasive identification of adherent-invasive E. coli in patients with Crohn’s disease

Journal of Crohn s and Colitis ◽

10.1093/ecco-jcc/jjz203.045 ◽

2020 ◽

Vol 14 (Supplement_1) ◽

pp. S044-S045 ◽

Cited By ~ 1

Author(s):

A Buisson ◽

E Vazeille ◽

X Hébuterne ◽

M Fumery ◽

B Pariente ◽

...

Keyword(s):

Crohn’S Disease ◽

Crohn's Disease ◽

Unmet Need ◽

Inhibition Test ◽

Invasive Ability ◽

Ileal Mucosa ◽

Multi Centre Study ◽

E Coli ◽

Non Invasive ◽

Adhesion Inhibition

Abstract Background Medications limiting the adhesion of ‘adherent and invasive E. coli’ (AIEC) represent potential strategies to treat Crohn’s disease (CD). However, the ileal AIEC identification is a time-consuming procedure, and the number of AIEC strains which colonise ileal CD mucosa remains unknown. There is an unmet need for non-invasive biomarkers to identify patients colonised by AIEC. We aimed to evaluate non-invasive biomarker of ileal AIEC colonisation in patients with CD. Methods This prospective and multi-centre study included CD patients requiring ileocoloscopy. Saliva, serum, stools and ileal biopsies were collected. Abundance and global invasive ability of ileal or faecal E. coli were performed. Isolated E. coli were characterised as AIEC or non-AIEC on I407 epithelial cells and THP1 macrophages. The ERIC-PCR profiles of ileal E. coli were performed. Ileal E. coli/CEACAM6 interaction was analysed by a yeast aggregation test and T84 assays (CEACAM6 protein expression, adhesion inhibition test with D-mannose). Quantification of serum anti-E. coli and ileal or salivary CEACAM6 was realised by ELISA. Results Overall, 102 CD patients were enrolled in this study and 25.8% of them exhibited ileal AIEC colonisation (AIEC+). The abundance and global invasive ability of ileal mucosa-associated E. coli were higher in AIEC+ CD patients compared with CD patients without AIEC (AIEC−) (p = 0.0065 and p = 0.0007, respectively). There was no difference between faecal abundance and invasive ability of E. coli between AIEC+ and AIEC− patients. The ERIC-PCR profiles of ileal E. coli showed that CD AIEC+ were for 78% of them colonised by not more than 2 clonal AIEC strains. In addition, AIEC were able to interact with CEACAM6 by binding D-mannose residues and to induce CEACAM6 expression in T84 cells (p = 0.0009 and p = 0.0185, vs. non-AIEC; respectively). This was also supported by adhesion inhibition test. Serum anti-E. coli level was higher for CD AIEC+ (vs. CD AIEC-). Ileal CEACAM6 level were positively correlated with abundance of ileal associated E. coli in AIEC+ patients (r = 0.4000; p = 0.0362) and with salivary CEACAM6 level (r = 0.4690; p < 0.0001). The non-invasive biomarker ‘serum anti-E.coli/salivary CEACAM6’ index was higher for CD AIEC+ (p = 0.0174; vs. CD AIEC-). A cut-off value < 1.34 × 10−6 eliminated the presence of ileal AIEC with a high negative predictive value (90% CI95% [69%–95%]). Conclusion Our study reported that identification of faecal AIEC cannot replace identification of AIEC from ileal biopsies, most of AIEC infection are mono or bi-clonal (≤ 2 strains) and that non-invasive biomarker such as ‘serum anti-E.coli/salivary CEACAM6’ index could be helpful to screen CD patients for AIEC infection.

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Corrigendum to “Let-7b ameliorates Crohn’s disease-associated adherent-invasive E coli induced intestinal inflammation via modulating Toll-Like Receptor 4 expression in intestinal epithelial cells” [Biochem. Pharmacol. 15 (2018) 196–203]

Biochemical Pharmacology ◽

10.1016/j.bcp.2018.09.025 ◽

2018 ◽

Vol 158 ◽

pp. 35-36

Author(s):

Zhen Guo ◽

Xingchen Cai ◽

Xian Guo ◽

Yihan Xu ◽

Jianfeng Gong ◽

...

Keyword(s):

Crohn’S Disease ◽

Crohn's Disease ◽

Epithelial Cells ◽

Intestinal Inflammation ◽

Intestinal Epithelial Cells ◽

Intestinal Epithelial ◽

Toll Like Receptor ◽

Toll Like Receptor 4 ◽

E Coli

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Adherent-Invasive E. coli: Update on the Lifestyle of a Troublemaker in Crohn’s Disease

International Journal of Molecular Sciences ◽

10.3390/ijms21103734 ◽

2020 ◽

Vol 21 (10) ◽

pp. 3734 ◽

Cited By ~ 2

Author(s):

Mélissa Chervy ◽

Nicolas Barnich ◽

Jérémy Denizot

Keyword(s):

Escherichia Coli ◽

Crohn’S Disease ◽

Crohn's Disease ◽

Genetic Factors ◽

Intestinal Epithelial Cells ◽

Intestinal Lumen ◽

Intestinal Epithelial ◽

E Coli ◽

The Subject ◽

The Impact

Besides genetic polymorphisms and environmental factors, the intestinal microbiota is an important factor in the etiology of Crohn’s disease (CD). Among microbiota alterations, a particular pathotype of Escherichia coli involved in the pathogenesis of CD abnormally colonizes the intestinal mucosa of patients: the adherent-invasive Escherichia coli (AIEC) pathobiont bacteria, which have the abilities to adhere to and to invade intestinal epithelial cells (IECs), as well as to survive and replicate within macrophages. AIEC have been the subject of many studies in recent years to unveil some genes linked to AIEC virulence and to understand the impact of AIEC infection on the gut and consequently their involvement in CD. In this review, we describe the lifestyle of AIEC bacteria within the intestine, from the interaction with intestinal epithelial and immune cells with an emphasis on environmental and genetic factors favoring their implantation, to their lifestyle in the intestinal lumen. Finally, we discuss AIEC-targeting strategies such as the use of FimH antagonists, bacteriophages, or antibiotics, which could constitute therapeutic options to prevent and limit AIEC colonization in CD patients.

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Blockage of bacterial FimH prevents mucosal inflammation associated with Crohn’s disease

Microbiome ◽

10.1186/s40168-021-01135-5 ◽

2021 ◽

Vol 9 (1) ◽

Author(s):

Grégoire Chevalier ◽

Arnaud Laveissière ◽

Guillaume Desachy ◽

Nicolas Barnich ◽

Adeline Sivignon ◽

...

Keyword(s):

Crohn’S Disease ◽

Crohn's Disease ◽

Gut Microbiome ◽

Bacterial Adhesion ◽

Intestinal Inflammation ◽

Mucosal Inflammation ◽

Intestinal Epithelial ◽

E Coli ◽

Promising Therapeutic Approach ◽

Activity Dependent

Abstract Background An Escherichia coli (E. coli) pathotype with invasive properties, first reported by Darfeuille-Michaud and termed adherent-invasive E. coli (AIEC), was shown to be prevalent in up to half the individuals with Crohn’s Disease (CD), suggesting that these bacteria could be involved in the pathophysiology of CD. Among the genes related to AIEC pathogenicity, fim has the potential to generate an inflammatory reaction from the intestinal epithelial cells and macrophages, as it interacts with TLR4, inducing the production of inflammatory cytokines independently of LPS. Therefore, targeting the bacterial adhesion of FimH-expressing bacteria seems a promising therapeutic approach, consisting of disarming bacteria without killing them, representing a selective strategy to suppress a potentially critical trigger of intestinal inflammation, without disturbing the intestinal microbiota. Results We analyzed the metagenomic composition of the gut microbiome of 358 patients with CD from two different cohorts and characterized the presence of FimH-expressing bacteria. To assess the pathogenic role of FimH, we used human intestinal explants and tested a specific FimH blocker to prevent bacterial adhesion and associated inflammation. We observed a significant and disease activity-dependent enrichment of Enterobacteriaceae in the gut microbiome of patients with CD. Bacterial FimH expression was functionally confirmed in ileal biopsies from 65% of the patients with CD. Using human intestinal explants, we further show that FimH is essential for adhesion and to trigger inflammation. Finally, a specific FimH-blocker, TAK-018, inhibits bacterial adhesion to the intestinal epithelium and prevents inflammation, thus preserving mucosal integrity. Conclusions We propose that TAK-018, which is safe and well tolerated in humans, is a promising candidate for the treatment of CD and in particular in preventing its recurrence.

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Lactobacillus casei DN-114 001 Inhibits the Ability of Adherent-Invasive Escherichia coli Isolated from Crohn's Disease Patients To Adhere to and To Invade Intestinal Epithelial Cells

Applied and Environmental Microbiology ◽

10.1128/aem.71.6.2880-2887.2005 ◽

2005 ◽

Vol 71 (6) ◽

pp. 2880-2887 ◽

Cited By ~ 52

Author(s):

Isabelle Ingrassia ◽

Antony Leplingard ◽

Arlette Darfeuille-Michaud

Keyword(s):

Crohn’S Disease ◽

Crohn's Disease ◽

Epithelial Cells ◽

Lactobacillus Casei ◽

Intestinal Epithelial Cells ◽

Probiotic Strain ◽

Intestinal Cells ◽

Intestinal Epithelial ◽

Inhibitory Effects ◽

E Coli

ABSTRACT Ileal lesions in 36.4% of patients with Crohn's disease are colonized by pathogenic adherent-invasive Escherichia coli. The aim of this study was to determine the in vitro inhibitory effects of the probiotic strain, Lactobacillus casei DN-114 001, on adhesion to and invasion of human intestinal epithelial cells by adherent-invasive E. coli isolated from Crohn's disease patients. The experiments were performed with undifferentiated Intestine-407 cells and with undifferentiated or differentiated Caco-2 intestinal epithelial cells. Bacterial adhesion to and invasion of intestinal epithelial cells were assessed by counting CFU. The inhibitory effects of L. casei were determined after coincubation with adherent-invasive E. coli or after preincubation of intestinal cells with L. casei prior to infection with adherent-invasive E. coli. Inhibitory effects of L. casei on adherent-invasive E. coli adhesion to differentiated and undifferentiated intestinal epithelial cells reached 75% to 84% in coincubation and 43% to 62% in preincubation experiments, according to the cell lines used. Addition of L. casei culture supernatant to the incubation medium increased L. casei adhesion to intestinal epithelial cells and enhanced the inhibitory effects of L. casei. The inhibitory effects on E. coli invasion paralleled those on adhesion. This effect was not due to a bactericidal effect on adherent-invasive E. coli or to a cytotoxic effect on epithelial intestinal cells. As Lactobacillus casei DN-114 001 strongly inhibits interaction of adherent-invasive E. coli with intestinal epithelial cells, this finding suggests that the probiotic strain could be of therapeutic value in Crohn's disease.

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Enhanced E. coli LF82 Translocation through the Follicle-associated Epithelium in Crohn’s Disease is Dependent on Long Polar Fimbriae and CEACAM6 expression, and Increases Paracellular Permeability

Journal of Crohn s and Colitis ◽

10.1093/ecco-jcc/jjz144 ◽

2019 ◽

Vol 14 (2) ◽

pp. 216-229 ◽

Cited By ~ 7

Author(s):

Åsa V Keita ◽

Lina Yakymenko Alkaissi ◽

Elin B Holm ◽

Stéphanie D S Heil ◽

Benoit Chassaing ◽

...

Keyword(s):

Crohn’S Disease ◽

Crohn's Disease ◽

Paracellular Permeability ◽

Ileal Mucosa ◽

Clinical Recurrence ◽

Ussing Chambers ◽

E Coli ◽

Follicle Associated Epithelium ◽

Vitro Model

Abstract Background and Aims Patients with Crohn’s disease [CD] harbour an increased number of adherent-invasive E. coli [AIEC]. The strain LF82, identified in the ileal mucosa of CD patients, has been extensively studied for pathogenic mechanisms. However, understanding of the interaction of LF82 with the intestinal mucosa of CD patients is lacking. Methods Here, we investigated the importance of long polar fimbriae [LPF] type 1 pili and the carcinoembryonic antigen-related cell-adhesion molecule 6 [CEACAM6] for translocation of LF82 in an in vitro model of follicle-associated epithelium [FAE], and in the FAE and villus epithelium [VE] of patients with CD and controls, using Ussing chambers. Results Significantly greater LF82 passage occurred in the FAE model compared with in the VE Caco-2cl1 mono-culture. Moreover, bacterial translocation was inhibited by either LPF disruption or pre-incubation with anti-CEACAM6 antibody. Tissue mounted in Ussing chambers showed significantly higher LF82 passage in FAE from patients with CD compared with control FAE, that was diminished in LF82 lacking LPF and by blocking host CEACAM6. Interestingly, addition of LF82 to the CD FAE tissues significantly increased paracellular permeability [of 51Chromium-EDTA] compared with baseline, and the increase was inhibited by anti-CEACAM6. Immunofluorescence and immunoblots showed higher expression of CEACAM6 in FAE of patients with CD compared with in FAE from controls. Conclusions These data suggest that the FAE of CD patients is a site of vulnerability for invasion by LF82 via a mechanism that requires both bacterial LPF and host CEACAM6. Further, LF82 has the ability to increase paracellular passage through the FAE of patients with CD. These data can help define novel therapeutic targets in CD for the prevention of clinical recurrence.

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