scholarly journals Extracellular vesicles package dsDNA to aggravate Crohn’s disease by activating the STING pathway

2021 ◽  
Vol 12 (9) ◽  
Author(s):  
Fan Zhao ◽  
Tao Zheng ◽  
Wenbin Gong ◽  
Jie Wu ◽  
Haohao Xie ◽  
...  
Keyword(s):  
Crohn’S Disease ◽  
Crohn's Disease ◽  
Extracellular Vesicles ◽  
Intestinal Inflammation ◽  
Therapeutic Effects ◽  
Murine Colitis ◽  
Sting Pathway ◽  
Deficient Mice

AbstractCrohn’s disease (CD) is an intestinal immune-dysfunctional disease. Extracellular vesicles (EVs) are membrane-enclosed particles full of functional molecules, e.g., nuclear acids. Recently, EVs have been shown to participate in the development of CD by realizing intercellular communication among intestinal cells. However, the role of EVs carrying double-strand DNA (dsDNA) shed from sites of intestinal inflammation in CD has not been investigated. Here we isolated EVs from the plasma or colon lavage of murine colitis and CD patients. The level of exosomal dsDNA, including mtDNA and nDNA, significantly increased in murine colitis and active human CD, and was positively correlated with the disease activity. Moreover, the activation of the STING pathway was verified in CD. EVs from the plasma of active human CD triggered STING activation in macrophages in vitro. EVs from LPS-damaged colon epithelial cells were also shown to raise inflammation in macrophages via activating the STING pathway, but the effect disappeared after the removal of exosomal dsDNA. These findings were further confirmed in STING-deficient mice and macrophages. STING deficiency significantly ameliorated colitis. Besides, potential therapeutic effects of GW4869, an inhibitor of EVs release were assessed. The application of GW4869 successfully ameliorated murine colitis by inhibiting STING activation. In conclusion, exosomal dsDNA was found to promote intestinal inflammation via activating the STING pathway in macrophages and act as a potential mechanistic biomarker and therapeutic target of CD.

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

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.

scholarly journals Comorbid Inflammatory Diseases of Digestive System and Eye

2021 ◽  
Vol 18 (1) ◽  
pp. 20-29
Author(s):  
S. A. Bulgakov ◽  
G. M. Chernakova ◽  
E. A. Kleshcheva ◽  
S. V. Simonova
Keyword(s):  
Ulcerative Colitis ◽  
Crohn’S Disease ◽  
Crohn's Disease ◽  
Inflammatory Bowel Diseases ◽  
Intestinal Inflammation ◽  
Ophthalmological Examination ◽  
Extraintestinal Manifestations ◽  
Bowel Diseases ◽  
Inflammatory Bowel

Crohn’s disease and ulcerative colitis are chronic inflammatory bowel diseases, which are often accompanied by inflammation of other organs. This article presents modern data on etiology, pathogenesis and clinical course of inflammatory bowel diseases, as well as information on extraintestinal eye manifestations of nonspecific ulcerative colitis and Crohn’s disease. The role of microbiota, genetic factors, immune system defects in pathogenesis of intestinal inflammation and extraintestinal eye manifestations is considered. The possibility the development of ophthalmopathology not only against the background of intestinal inflammation, but also as a consequence of therapeutic and surgical methods of treatment of ulcerative colitis and Crohn’s disease is noted. The peculiarities of the course of episcleritis/scleritis, keratitis, uveitis, chorioretinitis, optical neuritis for patients with inflammatory bowel diseases are considered. The presence of these complications may reflect the activity of the underlying disease, which in some cases requires correction of therapy. Anterior uveitis and episcleritis/scleritis are the most common extraintestinal manifestations of inflammatory bowel disease. Inflammation of tissues of the posterior segment of the eye and optic nerve against the background of ulcerative colitis and Crohn’s disease are less common, but are of clinical importance, as they can catastrophically damage the structures of the eye and, as a consequence, lead to complete blindness. Considering the possibility of mild clinical symptoms and asymptomatic course of inflammation in the eye envelopes, the importance of ophthalmological examination of all patients with ulcerative colitis and Crohn’s disease is emphasized. Aspects of modern therapy of ophthalmopathology and background intestinal inflammation are highlighted. Biological preparations — antagonists of pro-inflammatory cytokines — have been identified as the most promising in the treatment of inflammatory intestinal diseases and extraintestinal manifestations. The important role of proper nutrition and biologically active supplements containing omega-3 fatty acids, vitamin D, microelements, was noted as auxiliary therapy of both intestinal and extraintestinal inflammation.

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.

Calprotectin or Lactoferrin: Do They Help

2016 ◽  
Vol 34 (1-2) ◽  
pp. 98-104 ◽  
Author(s):  
Emily K. Wright
Keyword(s):  
Ulcerative Colitis ◽  
Crohn’S Disease ◽  
Crohn's Disease ◽  
Intestinal Inflammation ◽  
Gastrointestinal Symptoms ◽  
Treat To Target ◽  
Clinical Relapse ◽  
Markers Of Inflammation ◽  
Fecal Biomarkers

Background: The diagnosis and monitoring of inflammatory bowel disease (IBD) has traditionally relied on clinical assessment, serum markers of inflammation and endoscopic examination. Fecal biomarkers such as calprotectin (FC) and lactoferrin (FL) are predominantly derived from neutrophils, are easily detectable in the feces and are now established as valuable markers of intestinal inflammation. In recent years, a ‘treat to target' concept has emerged for the management of IBD. Adequate control of inflammation in IBD at a biochemical level is quickly becoming an important target in IBD management. Key Messages: Fecal biomarkers have been shown to be significantly and consistently increased in both adult and pediatric patients with IBD versus those without IBD. Fecal biomarkers are therefore useful in determining those patients with gastrointestinal symptoms who are likely to benefit from colonoscopy versus those in whom colonoscopy is likely to be normal. Fecal biomarkers correlate significantly with endoscopic disease in both Crohn's disease and ulcerative colitis. Suggested cutoffs for FC for endoscopically active disease in IBD range from 50 to 280 μg/g. Fecal biomarkers reflect the success of treatment intensification and can help predict clinical relapse. Both FC and FL are accurate in the detection of postoperative endoscopic recurrence of Crohn's disease, and FC may be clinically useful in predicting those patients with acute severe ulcerative colitis who may progress to colectomy. There are limitations to these fecal tests including a false positive rate and intra-individual variability. Conclusions: This review focuses on the role of fecal biomarkers in the diagnosis, monitoring and management of IBD and how best to interpret results. We will discuss the emerging role of these biomarkers in the IBD management landscape including FC-guided drug dosing and the development of home-based testing and e-health applications. Fecal biomarker results must always be interpreted in a clinical context. Endoscopic assessment remains the gold standard for diagnosis and monitoring of IBD.

scholarly journals Correction: Extracellular vesicles package dsDNA to aggravate Crohn’s disease by activating the STING pathway

2021 ◽  
Vol 12 (11) ◽  
Author(s):  
Fan Zhao ◽  
Tao Zheng ◽  
Wenbin Gong ◽  
Jie Wu ◽  
Haohao Xie ◽  
...  
Keyword(s):  
Crohn’S Disease ◽  
Crohn's Disease ◽  
Extracellular Vesicles ◽  
Sting Pathway

scholarly journals Tumor Necrosis Factor’s Pathway in Crohn’s Disease: Potential for Intervention

2021 ◽  
Vol 22 (19) ◽  
pp. 10273
Author(s):  
Cristiano Pagnini ◽  
Fabio Cominelli
Keyword(s):  
Crohn’S Disease ◽  
Crohn's Disease ◽  
Tumor Necrosis ◽  
Intestinal Inflammation ◽  
Innate Immune Responses ◽  
Chronic Disorder ◽  
Near Future ◽  
Necrosis Factor ◽  
Open Issues

Crohn’s disease (CD) is a chronic disorder characterized by full thickness patchy inflammation of the gastrointestinal tract. The pathogenesis is multifactorial and involves defective innate immune responses, microbiome alterations, and dysregulated activation of the acquired component of mucosal immunity. One of the molecular mediators that is involved at different levels in the initiation and progression of intestinal inflammation characteristic of CD is tumor necrosis factor (TNF). The present manuscript provides a comprehensive review focused on the potential role of TNF in the different phases of CD pathogenesis, particularly in light of its potential clinical implications. Currently available drugs blocking TNF are evaluated and discussed, specifically for open issues that still remain utilizing such therapy. TNF exerts a paramount role in the established phase of intestinal inflammation that characterizes CD patients, and anti-TNF biologics have definitely changed patient management, offering effective and safe options of treatment. Nonetheless, many patients still do not respond to anti-TNF therapy or experience unwanted side-effects. This could partially be due to the role that TNF plays in intestinal homeostasis that is particularly important during the early phase of the inflammatory process. In fact, emerging evidence supporting the dichotomous role of TNF and the identification of molecular markers will guide a more tailored and refined therapy for CD patients in the near future.

scholarly journals The Possible Pathogenic Role of IgG4-Producing Plasmablasts in Stricturing Crohn’s Disease

Pathobiology ◽  
2022 ◽  
pp. 1-11
Author(s):  
Omar Bushara ◽  
David Joseph Escobar ◽  
Samuel Edward Weinberg ◽  
Leyu Sun ◽  
Jie Liao ◽  
...  
Keyword(s):  
Crohn’S Disease ◽  
Crohn's Disease ◽  
Intestinal Inflammation ◽  
Adaptive Immune Response ◽  
Stricture Formation ◽  
Tfh Cells ◽  
Follicular Helper ◽  
The Us ◽  
Inflammatory Bowel

<b><i>Background:</i></b> Crohn’s disease (CD) is a condition on the spectrum of inflammatory bowel disease that affects up to 20 people per 100,000 in the US annually, and with incidence increasing. One of the most significant sources of morbidity in CD is the formation of strictures, with resultant intestinal blockage a common indication for hospitalization and surgical intervention in these patients. The pathophysiology of stricture formation is not fully understood. However, the fibroplasia that leads to fibrostenotic stricture formation may have shared pathophysiology with IgG4-related fibrosis. <b><i>Summary:</i></b> Initial intestinal inflammation recruits innate immune cells, such as neutrophils, that secrete IL-1β and IL-23, which induces a type 17 CD4+ T-helper T-cell (Th17)-mediated adaptive immune response. These CD4+ Th17 T cells also contribute to inflammation by secreting proinflammatory cytokines such as IL-17 and IL-21. IL-21 recruits and stimulates CD4+ T follicular helper (Tfh) cells, which secrete more IL-21. This causes ectopic germinal center formation, recruiting and stimulating naïve B cells. The IL-17 and IL-21 produced by Th17 cells and Tfh cells also induce IgG4 plasmablast differentiation. Finally, these IgG4-producing plasmablasts secrete platelet-derived growth factor (PDGF), which activates local PDGF-receptor expressing fibroblasts and myofibroblasts, resulting in uncontrolled fibroplasia.

The role of in vitro interferonγ-release assay in differentiating intestinal tuberculosis from Crohn's disease in China

2012 ◽  
Vol 6 (3) ◽  
pp. 317-323 ◽  
Author(s):  
Yue Li ◽  
Li-fan Zhang ◽  
Xiao-qing Liu ◽  
Li Wang ◽  
Xi Wang ◽  
...  
Keyword(s):  
Crohn’S Disease ◽  
Crohn's Disease ◽  
Intestinal Tuberculosis ◽  
Release Assay

scholarly journals Recent Advances in Diagnosis and Management of Crohn’s Disease

2021 ◽  
Author(s):  
Anjana Bali ◽  
Monika Rani
Keyword(s):  
Inflammatory Bowel Disease ◽  
Crohn’S Disease ◽  
Crohn's Disease ◽  
Intestinal Inflammation ◽  
Inflammatory Cascade ◽  
Recent Advances ◽  
Mucosal Edema ◽  
Inflammatory Bowel ◽  
Assessment Of Disease Activity

The initiation of Crohn’s disease, an inflammatory bowel disease, has been primarily associated with crypt inflammation and abscesses, which further progresses towards the development of mucosal lesion and ulcers followed by mucosal edema. Despite many years of research for the confirmatory role of inflammation in this disease, various pathways and diagnosis for this inflammatory cascade is still unrevealed, which in fact is of utmost importance in the assessment of disease activity and for tailoring the therapy. Till now, various histopathological as well as endoscopic examinations has been found to be effectively and accurately assess inflammatory activity, but they are invasive, time consuming and expensive and therefore are unsuitable for routine use. Consequently, the latest research is focusing on various biomarkers of intestinal inflammation and the corresponding biological therapy. So, this chapter will cover the recent advances in diagnosis and pharmacological therapies for the same.

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