Project description:The interpretation of transcriptional profiling studies of intestinal tissue from Crohn’s disease patients and control patients can be confounded by differing proportions of cell subsets (e.g. immune cells) present in these samples. In this study, we aimed to control for cellular composition using standard, archival formalin-fixed, paraffin-embedded (FFPE) tissue specimens from Crohn’s patients (n=36) and controls (n=32) who underwent intestinal resection surgery. This approach allowed us to use the same tissue specimens for histological screening to select study samples with similar cellular composition and for RNA extraction for RNA-seq transcriptional profiling. We hypothesized that this approach would allow us to more clearly identify molecular signatures in ileal tissue that were associated with Crohn’s disease-associated pathological mechanisms.
Project description:Based on genetic risk factors and natural history, Crohn’s disease (CD) can be separated in two entities, an ileal and a colonic disease. Protein based-approaches are needed to elucidate whether such subphenotypes are related to distinct pathophysiological processes. In this work, we compared the proteome of ulcer edge to the one of paired control tissue in ileum and colon of CD patients. We revealed that ileal and colonic ulcer edge can be distinguished by a differential distribution of epithelial–mesenchymal transition proteins, neutrophil degranulation proteins and ribosomal proteins. In ileal and colonic ulcer edge, we found a quasi-systematic increase of the proteins implicated in the pathway of protein processing in endoplasmic reticulum and a quasi-systematic decrease of mitochondrial proteins. Our study provides for the first time protein-based evidences showing partly distinct pathophysiological processes associated to ileal and colonic ulcer edge in CD. This could constitute a first step toward the development of gut segment-specific diagnostic markers and therapeutics.
Project description:Purpose: To identify the impact of 2'-FL supplementation on adaptive response following extensive intestinal resection. Methods: Transcriptomic profiles were obtained from mice undergoing ileocecal recection (8-10 week old male mice) and again at 8 weeks post-surgery. At the time of resection and again at 8 weeks post-op, small bowel samples were obtained from treatment and control animals and submitted for mRNA profiling. During these 8 weeks treatment animals (n=3) received 2'-FL supplementationion while controls (n=3) received only standard diet. Results: We observe enrichment in genes and pathways related to anti-microbial peptides, metabolism, and energy processing. Supplementation of 2'-FL increases energy availability and enhances the adaptive response. Male C57BL/6 mice at 8 to 10 weeks of age were submitted to ileocecal recection. Following resection, half were supplemented with 2'-FL for 8 weeks; small bowels were obtained and submitted for mRNA profiling,
Project description:The aim of this study is to identify early pathogenic changes in ileal gene expression that precede the development of macroscopic disease in inflammatory bowel diseases (IBDs). We focused on two IBD phenotypes that were unlikely to overlap: 1) ileal Crohn’s disease (CD) patients undergoing initial ileocolic resection of diseased ileum; and 2) ulcerative colitis (UC) patients undergoing total colectomy. The Control patients were those patients without IBD undergoing initial right hemicolectomy or total colectomy.
Project description:In Crohn’s disease (CD) pathology, we observed that: 1) a continuous process of fibrosis includes all the layers of the intestine as well as the surrounding mesenteric adipose tissue (MAT); 2) the amount of fibrosis in the MAT varies between samples even within a single case. To further investigate the molecular features of this fibrosis pattern, we did a paired study using formalin-fixed, paraffin-embedded blocks from ileocolonic resection specimens of seven CD patients. Specifically, one block contained ≥10% fibrosis amount while the other block contained <10% fibrosis amount within the MAT from the same case. MAT was selectively collected from serial histologic sections and total RNA was extracted for the Agilent Microarray analysis.
Project description:Crohn’s disease (CD) is a debilitating gastrointestinal disorder that can impact the entirety of the GI tract. While substantial progress has been made in the medical management of CD, it remains incurable, frequently relapses, and is a significant financial and medical burden. The pathophysiology of CD is not well understood, but it is thought to arise in genetically susceptible individuals upon an environmental insult. Further elucidation of the disease etiology promises to expose additional therapeutic avenues, with the hope of reducing the burden of CD. One approach to understanding disease pathophysiology is to identify clinically relevant molecular disease subsets using transcriptomics. In this report, we use hierarchical clustering of the ileal transcriptomes of 34 patients to identify two CD subsets. Clinically, these clusters differed in the age of the patients at CD diagnosis, suggesting that age of disease onset impacts the pathophysiology of the disease. We found that the ileal transcriptomes of the early diagnosis cluster are enriched in inflammatory transcripts, including S100A9, which encodes a calprotectin subunit. Furthermore, levels of S100A9 distinguished individuals diagnosed before the age of 30 from those diagnosed after 30. Together, these findings suggest that medical management of CD patients should consider their age at diagnosis and therapeutic blockade of calprotectin may be beneficial in patients diagnosed earlier in life.
Project description:Crohn’s disease is a chronic, debilitating inflammatory bowel disease. Here we report a critical role for phospholipase C-β3 (PLC-β3) in intestinal homeostasis. In PLC-β3- deficient mice, exposure to oral dextran sodium sulfate induced lethality and severe inflammation in the small intestine. The lethality was due to PLC-β3 deficiency in multiple non-hematopoietic cell types. PLC-β3 deficiency resulted in reduced Wnt/β-catenin signaling, which is essential for homeostasis and regeneration of the intestinal epithelium. PLC-β3 regulated the Wnt/β-catenin pathway in small intestinal epithelial cells (IECs) at transcriptional, epigenetic, and potentially protein-protein interaction levels. PLC-β3- deficient IECs were unable to respond to stimulation by R-spondin 1, an enhancer of Wnt/β-catenin signaling. Reduced expression of PLC-β3 and its signature genes was found in biopsies of ileal Crohn’s disease patients. PLC-β regulation of Wnt signaling was evolutionally conserved in Drosophila. Our data indicate that reduction of PLC-β3- mediated Wnt/β-catenin signaling contributes to the pathogenesis of ileal Crohn’s disease.
Project description:Crohn’s disease is a chronic, debilitating inflammatory bowel disease. Here we report a critical role for phospholipase C-β3 (PLC-β3) in intestinal homeostasis. In PLC-β3- deficient mice, exposure to oral dextran sodium sulfate induced lethality and severe inflammation in the small intestine. The lethality was due to PLC-3 deficiency in multiple non-hematopoietic cell types. PLC-β3 deficiency resulted in reduced Wnt/-catenin signaling, which is essential for homeostasis and regeneration of the intestinal epithelium. PLC-β3 regulated the Wnt/β-catenin pathway in small intestinal epithelial cells (IECs) at transcriptional, epigenetic, and potentially protein-protein interaction levels. PLC-β3- deficient IECs were unable to respond to stimulation by R-spondin 1, an enhancer of Wnt/β-catenin signaling. Reduced expression of PLC-β3 and its signature genes was found in biopsies of ileal Crohn’s disease patients. PLC-β regulation of Wnt signaling was evolutionally conserved in Drosophila. Our data indicate that reduction of PLC-β3- mediated Wnt/β-catenin signaling contributes to the pathogenesis of ileal Crohn’s disease.
Project description:Crohn’s disease is a chronic, debilitating inflammatory bowel disease. Here we report a critical role for phospholipase C-β3 (PLC-β3) in intestinal homeostasis. In PLC-β3- deficient mice, exposure to oral dextran sodium sulfate induced lethality and severe inflammation in the small intestine. The lethality was due to PLC-3 deficiency in multiple non-hematopoietic cell types. PLC-β3 deficiency resulted in reduced Wnt/-catenin signaling, which is essential for homeostasis and regeneration of the intestinal epithelium. PLC-β3 regulated the Wnt/β-catenin pathway in small intestinal epithelial cells (IECs) at transcriptional, epigenetic, and potentially protein-protein interaction levels. PLC-β3- deficient IECs were unable to respond to stimulation by R-spondin 1, an enhancer of Wnt/β-catenin signaling. Reduced expression of PLC-β3 and its signature genes was found in biopsies of ileal Crohn’s disease patients. PLC-β regulation of Wnt signaling was evolutionally conserved in Drosophila. Our data indicate that reduction of PLC-β3- mediated Wnt/β-catenin signaling contributes to the pathogenesis of ileal Crohn’s disease.
Project description:Crohn’s Disease (CD) pathogenesis is still unclear. Disorders in the mucosal immunoregulation and its crosstalk with the microbiota may represent an important component in tissue injury. We aimed to characterize the molecular immune response distribution within the ileal layers ( mucosa, submucosa and serosa) and to evaluate the correlated microbiota in pathological/healthy settings comparing first surgery/relapse clinical conditions.