Project description:This study investigates the presence of specific fibrosis-associated gene expression signatures in Crohn's disease patient biopsies.
Project description:Management of terminal ileal Crohn's disease (CD) is difficult due to fibrotic prognosis and failure to achieve mucosal healing. A limited number of synchronous analyses have been conducted on the transcriptome and microbiome in unpaired terminal ileum tissues. Therefore, our study focused on the transcriptome and mucosal microbiome in terminal ileal tissues of CD patients with the aim of determining the role of cross-talk between the microbiome and transcriptome in the pathogenesis of terminal ileal CD. Mucosa-attached microbial communities were significantly associated with segmental inflammation status. Interaction-related transcription factors (TFs) are the panel nodes for crosstalk between the gene patterns and microbiome for terminal ileal CD. The transcriptome and microbiome in terminal ileal CD can be different related to local inflammatory status, and specific differentially expressed genes (DEGs) may be targeted for mucosal healing. TFs connect gene patterns with the microbiome by reflecting environmental stimuli and signals from microbiota.
Project description:To use surgical resection specimens of the intact bowel wall from inflammatory bowel disease (IBD) patients and perform RNA-seq, bioinformatics analysis, and validation by quantitative polymerase chain reaction (qPCR) and immunohistochemistry (IHC) to explore the subtle differences between Crohn's disease (CD) and ulcerative colitis (UC), with predominant focus on the smooth muscle cells (SMCs) and enteric autonomic nervous system (ANS).
Project description:<p>This UH2/UH3 demonstration project entitled "Effects of Crohn's disease risk alleles on enteric microbiota" is focused on characterizing intestinal associated microbiota in patients with ileal Crohn's disease (ileal CD), ulcerative colitis (UC) and control patients without inflammatory bowel diseases (non-IBD). We hypothesize that genetic factors that affect Paneth cell function, contribute to compositional changes in intestinal microbiota. These changes in microbiota may lead to reduction of protective commensal organisms and increased numbers of aggressive organisms that incite intestinal inflammation. This hypothesis is being tested by high throughput 16S rRNA sequence analysis of de-identified ileal and colonic tissues that have been archived at Washington University St. Louis, University of North Carolina, Mount Sinai Hospital and the Cleveland Clinic. Multivariate analysis of the metagenomic data will be conducted with genotyping metadata (highly reproducible CD risk alleles, including NOD2 and ATG16L1) and phenotyping metadata (e.g. age, gender, race, body mass index, medications and smoking.)</p> <p>Shotgun sequencing will be performed on selected fecal specimens linked to ileal tissues to identify additional, or auxiliary, or synergistic pathogenic factors or other functional changes in the microbiome. Because members of this research team have observed that a chronic viral infection is required for the Paneth cell defect in Atg16l1 hypomorphic mice, a major focus of these studies will be towards identifying potential viral triggers for the defective Paneth cell phenotype in individuals harboring the ATG16L1 risk allele. Novel genetic probes for protective and aggressive organisms will be developed by mining bacterial genome and shotgun sequencing data. Genomic sequences will be produced for candidate protective and aggressive strains (e.g. adherent-invasive strains of E. coli) isolated from human intestinal tissues where there is limited existing genome information. Quantitative qPCR assays using the novel as well as established genetic probes will be conducted to test the hypothesis that an imbalance between protective and aggressive organisms is associated with genetic factors that affect Paneth cell function.</p> <p>Our combined expertise in multiple disciplines across multiple institutions, our demonstrated ability to collect a large number of well-phenotyped samples with longitudinal clinical information that will be linked to host response and morphologic studies, and our consortium's capacity for high-throughput sequencing will be used to investigate how alterations in human microbiome relate to CD risk alleles and CD pathogenesis.</p>