275 Saccharomyces Cerevisiae as a Therapeutic Tool to Prevent Colonization of the Gut by Adherent-Invasive E. coli in Crohn's Disease Patients

ABSTRACTCrohn’s disease (CD) results from a complex interplay between host genetic factors and endogenous microbial communities. In the current study, we used Ion Torrent sequencing to characterize the gut bacterial microbiota (bacteriome) and fungal community (mycobiome) in patients with CD and their nondiseased first-degree relatives (NCDR) in 9 familial clusters living in northern France-Belgium and in healthy individuals from 4 families living in the same area (non-CD unrelated [NCDU]). Principal component, diversity, and abundance analyses were conducted, and CD-associated inter- and intrakingdom microbial correlations were determined. Significant microbial interactions were identified and validated using single- and mixed-species biofilms. CD and NCDR groups clustered together in the mycobiome but not in the bacteriome. Microbiotas of familial (CD and NCDR) samples were distinct from those of nonfamilial (NCDU) samples. The abundance ofSerratia marcescensandEscherichia coliwas elevated in CD patients, while that of beneficial bacteria was decreased. The abundance of the fungusCandida tropicaliswas significantly higher in CD than in NCDR (P= 0.003) samples and positively correlated with levels of anti-Saccharomyces cerevisiaeantibodies (ASCA). The abundance ofC. tropicaliswas positively correlated withS. marcescensandE. coli, suggesting that these organisms interact in the gut. The mass and thickness of triple-species (C. tropicalisplusS. marcescensplusE. coli) biofilm were significantly greater than those of single- and double-species biofilms.C. tropicalisbiofilms comprised blastospores, while double- and triple-species biofilms were enriched in hyphae.S. marcescensused fimbriae to coaggregate or attach withC. tropicalis/E. coli, whileE. coliwas closely apposed withC. tropicalis. Specific interkingdom microbial interactions may be key determinants in CD.IMPORTANCEHere, we characterized the gut bacterial microbiota (bacteriome) and fungal community (mycobiome) in multiplex families with CD and healthy relatives and defined the microbial interactions leading to dysbiosis in CD. We identified fungal (Candida tropicalis) and bacterial (Serratia marcescensandEscherichia coli) species that are associated with CD dysbiosis. Additionally, we found that the level of anti-Saccharomyces cerevisiaeantibodies (ASCA; a known CD biomarker) was associated with the abundance ofC. tropicalis. We also identified positive interkingdom correlations betweenC. tropicalis,E. coli, andS. marcescensin CD patients and validated these correlations usingin vitrobiofilms. These results provide insight into the roles of bacteria and fungi in CD and may lead to the development of novel treatment approaches and diagnostic assays.

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Macrophages behaviour against Adherent and Invasive E. coli (AIEC) isolated from Crohn's disease patients in relation with host factors susceptibility

10.26226/morressier.57c5383ed462b80296c9b40e ◽

2016 ◽

Author(s):

Anthony Buisson

Keyword(s):

Crohn’S Disease ◽

Crohn's Disease ◽

Host Factors ◽

E Coli

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The Order in Which Antibiotics are Administered Affects the Fitness Costs of Adherent-Invasive E. coli (AIEC) Strains

10.31219/osf.io/46fae ◽

2019 ◽

Author(s):

Jordan B Gregg

Keyword(s):

Crohn’S Disease ◽

Crohn's Disease ◽

Combination Therapy ◽

Agar Plate ◽

Sequential Therapy ◽

Negative Control ◽

Clinical Settings ◽

Fitness Costs ◽

Inflammatory Gene Expression ◽

E Coli

AIEC-LF82 is a strain of bacteria that is surmised to have a role in causing IBD and Crohn’s disease by activating pro-inflammatory gene expression in organisms. Using antibiotics via combination therapy has been a technique used in clinical settings in an attempt to treat the strains, however, the attempts have not been that effective nor efficient in terms of completely halting the growth and colonization of AIEC to treat IBD and Crohn's disease patients. Research has shown that regarding hindering or preventing the colonization bacterial colonies, sequential therapy tends to be more effective and time-efficient than combination therapy, with fewer adverse effects. To test if this is also the case with the AIEC-LF82 strain of bacteria, I first tested AIEC’s response to combination therapy using the Penicillin-Streptomycin, Kanamycin-Chloramphenicol, antimicrobial peptide (AMP), Kanamycin, SPE phase and LB agar plates, all of which were experimental plates other than the LB agar plate that acted as the negative control. I then tested AIEC-LF82’s response to sequential therapy using the LB+ Kan + Spe, LB + AMP + Spe, LB+ Kan/Cam + Spe, LB + P/S + Spe, LB + P/S + Kan and LB + P/S + AMP and one LB agar plate acting as the negative control. The only differences between sets a and b were the order in which antibiotics were administered in the six aforementioned treatment sets. Ultimately, I found that set b of sequential therapy, strong-weak antibiotic treatments, was the most effective treatment but that set a regarding sequential therapy was actually the least effective of all of the treatments. In conclusion, using strong-weak sequential antibiotic therapy treatments appears to be a potentially promising option to treat patients suffering from Crohn's disease and IBD.

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Antagonism of Adherent Invasive E. coli LF82 With Human α-defensin 5 in the Follicle-associated Epithelium of Patients With Ileal Crohn’s Disease

Inflammatory Bowel Diseases ◽

10.1093/ibd/izaa315 ◽

2020 ◽

Author(s):

Lina Y Alkaissi ◽

Martin E Winberg ◽

Stéphanie DS Heil ◽

Staffan Haapaniemi ◽

Pär Myrelid ◽

...

Keyword(s):

Crohn’S Disease ◽

Crohn's Disease ◽

Ex Vivo ◽

Ussing Chambers ◽

E Coli ◽

Follicle Associated Epithelium ◽

Vitro Model ◽

Set Up

Abstract Background The first visible signs of Crohn’s disease (CD) are microscopic erosions over the follicle-associated epithelium (FAE). The aim of the study was to investigate the effects of human α-defensin 5 (HD5) on adherent-invasive Escherichia coli LF82 translocation and HD5 secretion after LF82 exposure in an in vitro model of human FAE and in human FAE ex vivo. Methods An in vitro FAE-model was set up by the coculture of Raji B cells and Caco-2-cl1 cells. Ileal FAE from patients with CD and controls were mounted in Ussing chambers. The effect of HD5 on LF82 translocation was studied by LF82 exposure to the cells or tissues with or without incubation with HD5. The HD5 secretion was measured in human FAE exposed to LF82 or Salmonella typhimurium. The HD5 levels were evaluated by immunofluorescence, immunoblotting, and ELISA. Results There was an increased LF82 translocation across the FAE-model compared with Caco-2-cl1 (P < 0.05). Incubation of cell/tissues with HD5 before LF82 exposure reduced bacterial passage in both models. Human FAE showed increased LF82 translocation in CD compared with controls and attenuated passage after incubation with sublethal HD5 in both CD and controls (P < 0.05). LF82 exposure resulted in a lower HD5 secretion in CD FAE compared with controls (P < 0.05), whereas Salmonella exposure caused equal secretion on CD and controls. There were significantly lower HD5 levels in CD tissues compared with controls. Conclusions Sublethal HD5 reduces the ability of LF82 to translocate through FAE. The HD5 is secreted less in CD in response to LF82, despite a normal response to Salmonella. This further implicates the integrated role of antimicrobial factors and barrier function in CD pathogenesis.

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