Presentation on theme: "Cleveland Clinic Foundation, Cleveland, USA"— Presentation transcript:
1 Cleveland Clinic Foundation, Cleveland, USA Epigenetic regulation of IBD-associated fibrosis: potential for novel anti-fibrotic therapiesTammy Sadler1,2, Angela Ting3, Yaomin Xu4, Xiuli Liu5, Eleni Stylianou1,21Department of Pathobiology, Lerner Research Institute, and 2Department of Gastroenterology and Hepatology, Digestive Disease Institute, 3Genomic Medicine Institute, 4Department of Quantitative Health Sciences, 5Department of Anatomic Pathology.Cleveland Clinic Foundation, Cleveland, USA
2 Inflammatory Bowel Disease – etiology? Environmental factorsGenetic susceptibilityAbnormal interaction of commensal gut flora, epithelial barrier and innate immunityCrohn’s DiseaseInflammation of small bowel & colon: transmuralEPIGENETICS?Increased matrix depostion e.g.Type I collagen (COL1A1, COL1A2)FIBROSIS
3 Intestinal inflammation and fibrosis in IBD Gut floraApoptotic &necroticepithelial cellsGUT LUMENEpitheliumEndogenoussignalsMucosalinnate immune cellsCytokines, chemokinese.g TNFa, IL-8,TGFb, IL-1b, IL-17Epithelial barrier dysfunctionCytokinesSUBMUCOSAEndothelial cellsTYPE I COLLAGENMesenchymal cells/fibroblasts/myofibroblastsFIBROSIS
4 EpigeneticsHeritable changes in phenotype that are independent of changes to the DNA sequence2 examples: Histone modifications and DNA methylationEpigenetic mechanisms determine whether a gene is silenced or activated and allows the cell to adapt to environmental cues.Epigenetics bridges the gap between genotype and environment
6 Clinical Significance Epigenetic modifications required for Type I collagen gene expression and a fibrotic DNA methylome or epigenotype for CD could have diagnostic and prognostic utility.New mechanistic insights into clinically relevant mechanisms of disease pathogenesis could be provided.The conceptual framework for identification of therapeutic targets and selective and efficacious anti-fibrotic "epi-pharmaceuticals” that could prevent or treat fibrosis.
7 removed after 16 days + 10 day washoff COL1A2H4H3Ac16128TGFbCytokinesremoved after 16 days day washoff-1599bp-25bpIL1bTNFaMe95 days16 daysSpecific histone modifications are associated with induction of COL1A2 gene expression in intestinal EndoMT5ABCSadler et al Inflamm Bowel Dis 2013 in press
8 Hypothesis and AimsFibrosis-specific epigenetic signatures occur in the fibrotic intestine in IBD.This hypothesis will be tested by 2 specific aims:Aim 1. Determine the fibrosis-specific histone modification signature in human fibrotic intestine in IBD in vivo.Aim 2. Identify the fibrosis-specific DNA methylome that defines human intestinal fibrogenesis in IBD in vivo.
9 Research planYear 1Collect age and gender matched normal control and CD fibrotic tissue specimensOptimize conditions for ChIP of tissueEstablish conditions for isolation of fresh human fibroblastsDemonstrate feasibility of performing epigenetic analysis in fresh HIFYear 2ChIP assays of tissue and fresh HIF to define type I collagen specific histone modification signatureEmploy MBD-isolated genome sequencing (MiGS) to profile changes in DNA methylation in human fibroblasts from fibrotic intestine.Integrate methylome with fibrotic transcriptome
10 Intestinal tissue specimens procured during year 1 Tissue sourceDiagnosisNumber of specimensColonDiverticular disease7Polyps3UC inflamed8CD fibrotic10CD inflamed5Ileum1Ileocolic anastamosis4