scholarly journals An Infectious Disease Process within an Immune- Mediated Disease Process: Role of the Gastrointestinal Microbiota in Crohn's Disease

Author(s):  
Gilles RG Monif
Author(s):  
Rasha Mostafa Mohamed Ali ◽  
Mai Bahgat Ibrahim Ghonimy

Abstract Background Crohn’s disease (CD) is a ruinous bowel disease, which, if left uncured, leads to penetrating bowel complications. Computed tomography enterography (CTE) is nowadays accepted as a principal modality for the assessment of small bowel diseases. The aim of this study is to assess the role of CT enterography in the identification of intramural as well as extra-intestinal CT changes yielding more thorough data about the level and severity of the disease process thus planning appropriate treatment strategy. Results From March 2017 to January 2019, 50 patients in Cairo, Egypt, who had clinical manifestations of inflammatory bowel disease, were evaluated by MDCTE. CT image analysis was processed, including anatomical localization of bowel segments affection, assessment of mucosal thickening and hyper-enhancement, and extra-enteric affection. Diagnosis of Crohn’s disease (CD) was confirmed by endoscopy and histopathology; mucosal thickening was seen in 42 patients (84%), mucosal hyper-enhancement was seen in 44 patients (88%) while engorgement of vasa recta (comb’s sign) was seen in 38 patients (76%). Conclusion Although ileocolonoscopy is a proven sensitive method to detect mucosal injury and diagnose disease activity, it is limited by its maximal extent and inability to detect transmural complications as well as limited ability to assess deep bowel wall involvement. CT enterography (CTE) is a valuable technique in diagnostic evaluation of intramural and extra-intestinal involvement in Crohn’s disease (CD) during disease activity.


2013 ◽  
Vol 2013 ◽  
pp. 1-8 ◽  
Author(s):  
Taha Rashid ◽  
Alan Ebringer ◽  
Clyde Wilson

There is a general consensus that Crohn’s disease (CD) develops as the result of immune-mediated tissue damage triggered by infections with intestinal microbial agents. Based on the results of existing microbiological, molecular, and immunological studies,Klebsiellamicrobe seems to have a key role in the initiation and perpetuation of the pathological damage involving the gut and joint tissues in patients with CD. Six different gastroenterology centres in the UK have reported elevated levels of antibodies toKlebsiellain CD patients. There is a relationship between high intake of starch-containing diet, enhanced growth of gut microbes, and the production of pullulanases byKlebsiella. It is proposed that eradication of these microbes by the use of antibiotics and low starch diet, in addition to the currently used treatment, could help in alleviating or halting the disease process in CD.


1990 ◽  
Vol 4 (7) ◽  
pp. 278-284 ◽  
Author(s):  
Stephan R Targan ◽  
Richard L Deem ◽  
Fergus Shanahan

Thirty years of research on the role of immune-mediated cytotoxic activity in the tissue injury of inflammatory bowel disease (IBD) has yielded only inconclusive data on the relevance of cytotoxic mechanisms. Two hypotheses have been advanced. One is that the destruction of target cells is mediated by direct recognition of target antigens by cytotoxic cells which in turn triggers lysis. Another hypothesis is that lysis occurs via an indirect bystander mechanism in which cells do not recognize a specific antigen on the target, but upon nonspecific activation release cytokines which are capable of lysing the target. The authors have investigated both hypotheses and studied the role of cytotoxic T cells and cytotoxic rectors released from activated T cells in the destruction of epithelial cells. Elevated levels of cytotoxic T cells were found in peripheral blood lymphocytes of patients with IBD, particularly Crohn's disease. The cytotoxic T cells were contained within the Leu 7+, CD8+ T cell subset and were detected using anti-CD3-triggered lysis. Increased cytotoxic T cell activity was also present within inflamed mucosa of patients with both Crohn's disease and ulcerative colitis. The specific targets of this activity have yet to be determined. Activation of mucosal T cells by antibodies to the T cell receptor (anti-CD3) in organ culture of normal fetal jejunum induces an enteropathy characterized by villous atrophy and crypt cell hyperplasia. This same change is seen near aphthous ulcers in patients with Crohn's disease. Soluble cytokines produced by T cells might be responsible for the mucosa! damage observed in these two models of mucosal injury. The goal of this study was to establish in vitro if cytotoxic cytokines can be released by triggering isolated colonic T cells, and what cytokine interactions are required for killing of colonic epithelial cells. These results demonstrate that human lamina propria lymphocyte T cells, triggered by addition of anti-CD3 and target cells, produce tumour necrosis factor-alpha and interferon-gamma, both of which are required for optimal killing of HT-29. Simultaneous release of these cytokines in the vicinity of epithelial cells during immune responses could play an important role in mucosal damage in IBD. The development of animal models and long term cultures of epithelial cells will allow many advances in research of the role of immune-mediated cytotoxicity in IBD.


2020 ◽  
Vol 158 (3) ◽  
pp. S21-S22
Author(s):  
Peilin Zhang ◽  
Lawrence Minardi ◽  
J. Todd Kuenstner ◽  
Steve Zekan ◽  
Rusty Kruzelock

2021 ◽  
Vol 27 (Supplement_1) ◽  
pp. S55-S55
Author(s):  
Marcin Sochal ◽  
Piotr Bialasiewicz ◽  
Agata Gabryelska ◽  
Renata Talar-Wojnarowska ◽  
Jakub Fichna ◽  
...  

Abstract Background and aims Serotonin affects intestinal physiology, mood, as well as circadian rhythm. Moreover, serotonin has proinflammatory function. Therefore, the aim of this study was to investigate the role of serotonin in clinical severity of Crohn’s Disease (CD) and its effect on pain and sleep quality. Methods Fifty-nine CD patients (34 in exacerbation and 25 in remission according to the Harvey-Bradshaw Index-HBI) and 25 health control individuals(HC) were recruited. Sleep quality was assessed by the Pittsburgh Sleep Quality Index (PSQI) and subjective severity of pain by the Visual Analog Scale (VAS). Seventeen patients were treated with anti-TNF-α induction therapy for 14 weeks. Results Serotonin level was higher in CD (145.12ng/mL, IQR:98.14–179.25) compared to HC (87.52ng/mL, IQR:70.04–129.39; p=0.002) and in exacerbation of CD (157.66ng/mL, IQR:111.94–197.64) compared to remission (122.33ng/mL, IQR:83.28–163.67; p=0.029). Serotonin level with cut-off point of 92.45 ng/mL is useful for distinguishing participants with CD from HC (sensitivity: 78%, specificity: 60%, positive predictive value: 82%). Positive correlation between serotonin and HBI (r=0.279, p=0.032) and severity of diarrhoea (r=0.260, p=0.047) were found. Serotonin does not correlate with PSQI (r=0.152, p=0.168), but correlates with presence of sleep fragmentation for example by getting up to use the bathroom (joined 5b-5j PSQI questions; r=0.270, p=0.039). Correlations between serotonin and VAS were also obtained (r=0.220, p=0.045). Moreover, serotonin level significantly decreased after anti-TNF-α therapy (192.35ng/mL, IQR:150.36–225.56 vs. 121.11ng/mL, IQR:91.28–188.87; p=0.006). The study was funded by National Science Centre, Poland (#2018/31/N/NZ5/03715). Conclusions Serotonin level correlates with the severity of CD and decreases after anti-TNF-α therapy. It is associated with sleep fragmentation, which may be caused by diarrhea.


2021 ◽  
Vol 13 (1) ◽  
Author(s):  
M. Hornschuh ◽  
E. Wirthgen ◽  
M. Wolfien ◽  
K. P. Singh ◽  
O. Wolkenhauer ◽  
...  

AbstractEpigenetics has become a promising field for finding new biomarkers and improving diagnosis, prognosis, and drug response in inflammatory bowel disease. The number of people suffering from inflammatory bowel diseases, especially Crohn's disease, has increased remarkably. Crohn's disease is assumed to be the result of a complex interplay between genetic susceptibility, environmental factors, and altered intestinal microbiota, leading to dysregulation of the innate and adaptive immune response. While many genetic variants have been identified to be associated with Crohn's disease, less is known about the influence of epigenetics in the pathogenesis of this disease. In this review, we provide an overview of current epigenetic studies in Crohn's disease. In particular, we enable a deeper insight into applied bioanalytical and computational tools, as well as a comprehensive update toward the cell-specific evaluation of DNA methylation and histone modifications.


Author(s):  
Lina Y Alkaissi ◽  
Martin E Winberg ◽  
Stéphanie DS Heil ◽  
Staffan Haapaniemi ◽  
Pär Myrelid ◽  
...  

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.


Sign in / Sign up

Export Citation Format

Share Document