Project description:Background & Aims: Genome-wide gene expression (GWGE) profiles of mucosal colonic biopsies have suggested the existence of a continuous inflammatory state in quiescent ulcerative colitis (UC). The aim of this study was to use DNA microarray-based GWGE profiling of mucosal colonic biopsies and isolated colonocytes from UC patients and controls in order to identify the cell types responsible for the continuous inflammatory state. Methods: Adjacent mucosal colonic biopsies were obtained endoscopically from the descending colon in patients with active UC (n=8), quiescent UC (n=9), and with irritable bowel syndrome (controls, n=10). After isolation of colonocytes and subsequent extraction of total RNA, GWGE data were acquired using Human Genome U133 Plus 2.0 GeneChip Array (Affymetrix, Santa Clara, CA). Data analysis was carried out by principal component analysis and projection to latent structure-discriminant analysis using the SIMCA-P11 software (Umetrics, Umeå, Sweden). Results: A clear separation between active UC, quiescent UC and control biopsies were found, whereas the model for the colonocytes was unable to distinguish between quiescent UC and controls. The differentiation between quiescent UC and control biopsies was governed by unique profiles containing gene expressions with significant fold changes. These primarily belonged to the family of homeostatic chemokines revealing a plausible explanation to the abnormal regulated innate immune response seen in patients with UC. Conclusion: This study has demonstrated the presence of a continuous inflammatory state in quiescent UC, which seems to reflect an altered gene expression profile of lamina propria cells. Keywords: Colonocytes, continuous inflammation, mucosal colonic biopsies, gene expression profiles
Project description:Background & Aims: Genome-wide gene expression (GWGE) profiles of mucosal colonic biopsies have suggested the existence of a continuous inflammatory state in quiescent ulcerative colitis (UC). The aim of this study was to use DNA microarray-based GWGE profiling of mucosal colonic biopsies and isolated colonocytes from UC patients and controls in order to identify the cell types responsible for the continuous inflammatory state. Methods: Adjacent mucosal colonic biopsies were obtained endoscopically from the descending colon in patients with active UC (n=8), quiescent UC (n=9), and with irritable bowel syndrome (controls, n=10). After isolation of colonocytes and subsequent extraction of total RNA, GWGE data were acquired using Human Genome U133 Plus 2.0 GeneChip Array (Affymetrix, Santa Clara, CA). Data analysis was carried out by principal component analysis and projection to latent structure-discriminant analysis using the SIMCA-P11 software (Umetrics, Umeå, Sweden). Results: A clear separation between active UC, quiescent UC and control biopsies were found, whereas the model for the colonocytes was unable to distinguish between quiescent UC and controls. The differentiation between quiescent UC and control biopsies was governed by unique profiles containing gene expressions with significant fold changes. These primarily belonged to the family of homeostatic chemokines revealing a plausible explanation to the abnormal regulated innate immune response seen in patients with UC. Conclusion: This study has demonstrated the presence of a continuous inflammatory state in quiescent UC, which seems to reflect an altered gene expression profile of lamina propria cells. Keywords: Colonocytes, continuous inflammation, mucosal colonic biopsies, gene expression profiles Adjacent mucosal colonic biopsies were attained endoscopically from the descending colon in patients with active UC (n=8), quiescent UC (n=9), and in controls (n=10). After extraction of total RNA, genome-wide gene expression data were acquired using Human Genome U133 Plus 2.0 GeneChip Array (Affymetrix, Santa Clara, CA). Amplification was required to obtain sufficient amounts of labelled complementary RNA (cRNA) target for analysis with arrays. Data analysis was carried out by principal component analysis and projection to latent structure-discriminant analysis using the SIMCA-P11 software (Umetrics, Umeå, Sweden).
Project description:The samples are a part of a study aiming at diagnosing ulcerative colitis from genome-wide gene expression analysis of the colonic mucosa. Colonic mucosal samples were collected as endoscopic pinch biopsies from ulcerative colitis patients and from control subjects. Samples with and without macroscopic signs of inflammation were collected from the patients. Keywords: Disease state analysis
Project description:The samples are a part of a study aiming at diagnosing ulcerative colitis from genome-wide gene expression analysis of the colonic mucosa. Colonic mucosal samples were collected as endoscopic pinch biopsies from ulcerative colitis patients and from control subjects. Samples with and without macroscopic signs of inflammation were collected from the patients. Experiment Overall Design: The series contain eight UC samples with macroscopic signs of inflammation, 13 UC smaples without macroscopic signs of inflammation, five control subjects.
Project description:Colonic epithelial cells facilitate host-microbe interactions to control mucosal immunity, and they also coordinate recycling and forming the mucus barrier. Epithelial barrier breakdown underpins inflammatory bowel disease (IBD). However, we do not know the specific contributions of each epithelial cell subtype to this process. Here, we profiled single colonic epithelial cells in health and IBD. Our results identified previously unknown subtypes and crypt gradients of progenitors, colonocytes and goblet cells. We also revealed a novel specialized metal ion storage and chloride secretory cell. In IBD, we discovered a unique cluster of disease associated goblet cells that remodels the barrier. We found downregulated WFDC2, a novel goblet cell expressing anti-protease that inhibited bacterial growth. Our in vivo studies demonstrated WFDC2 preserved tight junction integrity and prevented commensal invasion and mucosal inflammation. We delineate markers and transcriptional states, identify a new colonic epithelial cell and uncover fundamental principles of epithelial plasticity and barrier breakdown in IBD. Thus, our study reveals new therapeutic targets and disease-related mechanisms in IBD
Project description:Gene expression profiling of immortalized human mesenchymal stem cells with hTERT/E6/E7 transfected MSCs. hTERT may change gene expression in MSCs. Goal was to determine the gene expressions of immortalized MSCs.
Project description:Background and aims: Mucosal abnormalities are potentially important in the primary pathogenesis of ulcerative colitis (UC). We investigated the mucosal transcriptomic expression profiles of biopsies from patients with UC and healthy controls (HC), taken from macroscopically non-inflamed tissue from the terminal ileum and three colonic locations with the objective of identifying abnormal molecules that might be involved in disease development. Methods: Whole-genome transcriptional analysis was performed on intestinal biopsies taken from 24 UC, 26 HC and 14 patients with Crohn’s disease. Differential gene expression analysis was performed at each tissue location separately and results were then meta-analysed using Fisher’s method. Significantly differentially expressed genes were validated using qPCR. Gene location within the colon was determined using immunohistochemistry, subcellular fractionation, electron and confocal microscopy. DNA methylation was quantified by pyrosequencing. Results: Seven probes were abnormally expressed throughout the colon in UC patients with Family with sequence similarity member 5 C (FAM5C) being the most significantly underexpressed. Attenuated expression of FAM5C in UC was independent of inflammation, unrelated to phenotype or treatment, and remained low at rebiopsy approximately 23 months later. FAM5C is localised to the brush border of the colonic epithelium and expression is influenced by DNA methylation within its promoter. Conclusion: Genome-wide expression analysis of non-inflamed mucosal biopsies from UC patients identified FAM5C as significantly under-expressed throughout the colon in a major sub-set of patients with UC. Low levels of this gene could predispose to or contribute to the maintenance of the characteristic mucosal inflammation seen in this condition.
Project description:Infliximab, an anti-TNF-alpha monoclonal antibody, is an effective treatment for ulcerative colitis (UC) with over 60% of patients responding to treatment and up to 30% reaching remission. The mechanism of resistance to anti-TNF-alpha is unknown. This study used colonic mucosal gene expression to provide a predictive response signature for infliximab treatment in UC. Keywords: drug response Twenty-four patients with active UC, refractory to corticosteroids and/or immunosuppression, underwent colonoscopy with biopsies from diseased colon within a week prior to the first intravenous infusion of 5 mg infliximab per kg body weight. Response to infliximab was defined as endoscopic and histologic healing at 4-6 weeks after first infliximab treatment. Six control patients with normal colonoscopy were included. Total RNA was isolated from colonic mucosal biopsies, labelled and hybridized to Affymetrix Human Genome U133 Plus 2.0 Arrays.
Project description:Kynureninase is a member of a large family of catalytically diverse but structurally homologous pyridoxal 5'-phosphate (PLP) dependent enzymes known as the aspartate aminotransferase superfamily or alpha-family. The Homo sapiens and other eukaryotic constitutive kynureninases preferentially catalyze the hydrolytic cleavage of 3-hydroxy-l-kynurenine to produce 3-hydroxyanthranilate and l-alanine, while l-kynurenine is the substrate of many prokaryotic inducible kynureninases. The human enzyme was cloned with an N-terminal hexahistidine tag, expressed, and purified from a bacterial expression system using Ni metal ion affinity chromatography. Kinetic characterization of the recombinant enzyme reveals classic Michaelis-Menten behavior, with a Km of 28.3 +/- 1.9 microM and a specific activity of 1.75 micromol min-1 mg-1 for 3-hydroxy-dl-kynurenine. Crystals of recombinant kynureninase that diffracted to 2.0 A were obtained, and the atomic structure of the PLP-bound holoenzyme was determined by molecular replacement using the Pseudomonas fluorescens kynureninase structure (PDB entry 1qz9) as the phasing model. A structural superposition with the P. fluorescens kynureninase revealed that these two structures resemble the "open" and "closed" conformations of aspartate aminotransferase. The comparison illustrates the dynamic nature of these proteins' small domains and reveals a role for Arg-434 similar to its role in other AAT alpha-family members. Docking of 3-hydroxy-l-kynurenine into the human kynureninase active site suggests that Asn-333 and His-102 are involved in substrate binding and molecular discrimination between inducible and constitutive kynureninase substrates.