Mapping Disease Pathways for Biliary Atresia

绘制胆道闭锁的疾病途径

基本信息

批准号：
9904315
负责人：
RAKESH K. SINDHI
金额：
$ 50.42万
依托单位：
UNIVERSITY OF PITTSBURGH AT PITTSBURGH
依托单位国家：
美国
项目类别：
财政年份：
2017
资助国家：
美国
起止时间：
2017-04-01 至 2022-03-31
项目状态：
已结题

来源：
https://reporter.nih.gov/project-details/9904315
关键词：
Affect Alpha-mannosidase Animal Model Bile fluid Biliary Biliary Atresia Bioinformatics Biological Birth California Candidate Disease Gene Cardiac Caucasians Cell Mobility Child Childhood Cicatrix Cilia Collaborations Congenital Abnormality Congenital atresia of extrahepatic bile duct Data Analyses Development Developmental Gene Disease Pathway Embryo Epidermal Growth Factor Erinaceidae Etiology Excretory function Experimental Models Extrahepatic Gene Expression Regulation Gene Proteins Genes Genetic Predisposition to Disease Genomics Genotype Growth Factor Gene Heart Hepatic Hepatology Hospitals Human Impairment Inflammation Inflammatory Inflammatory Response International Knockout Mice Knowledge Lead Left Liver Liver Failure London Lung Maps Modeling Morphogenesis Mus Organ Pathogenesis Pathology Pathway interactions Pattern Pediatric Hospitals Phenotype Philadelphia Predisposition Public Health Refractory Resources SNP array Sampling Signal Pathway Signal Transduction Single Nucleotide Polymorphism Situs Inversus Small Interfering RNA Stress Stress Response Signaling Susceptibility Gene Systems Analysis Systems Biology Targeted Resequencing Techniques Testing Tissues Transforming Growth Factors Transplant-Related Disorder Transplantation Transplantation Surgery University resources Variant Work Zebrafish airway epithelium base bile duct bioinformatics resource biological adaptation to stress causal variant cell motility cilium biogenesis cohort college gene function genome wide association study knock-down liver transplantation member novel prevent protein protein interaction response targeted sequencing transcriptome transcriptome sequencing transplant centers whole genome

项目摘要

This project will map disease pathways for biliary atresia (BA), which has failed all therapy and requires liver transplantation (LTx), using genetic susceptibility as a common basis. BA causes liver failure at birth and accounts for up to half of all pediatric LTx, worldwide, but has an uncertain etiology. BA leads to scarred and atretic bile ducts, which fail to drain the liver. Some children also have anomalous left-right patterning of extrahepatic organs. Preliminary genome-wide association study (GWAS) of single nucleotide polymorphisms (SNPs) in BA cases, and other evidence from human BA and experimental models lead us to propose the following specific aims: Aim 1. We will confirm whether BA associates with SNPs in manosidase-1-α-2 (MAN1A2), and in genes which signal via hedgehog, epidermal and transforming growth factors and genes for ciliogenesis. These pathways are abnormal in liver from BA cases, zebrafish with knockdown of man1a2, and Man1a2 -/- (knockout) mice. We will identify novel potentially causal variants with targeted sequencing of significant SNP loci. Aim 2. We will confirm whether knockdown of man1a2 and other candidates induces biliary dysgenesis and cardiac and hepatic heterotaxy in zebrafish, impaired ciliogenesis in the ex vivo mouse airway epithelia model of ciliogenesis, and dysregulation of the abovementioned developmental pathways in the liver transcriptome. Aim 3. We will construct putative pathways for BA with those significant SNP loci and dysregulated genes which show interactions in an integrated systems analysis of data from Aims 1 and 2. These loci will also implicate aberrant inflammatory and stress responses. We will corroborate pathways with combined perturbations of a developmental gene with an inflammatory and a stress response gene in zebrafish and ex vivo ciliogenesis models. We expect that aberrant developmental, inflammatory and stress response signaling contributes to hepatic and extrahepatic BA. We will genotype the largest homogeneous cohort of 800 Caucasian BA cases with LTx from three of the world's largest pediatric LTx centers: the Children's Hospital of Pittsburgh, King's College Hospital, London, UK, Birmingham Children's Hospital, UK. We will perform whole genome transcriptome (RNA) sequencing of liver samples from 80 of these cases. We will use experimental and bioinformatics resources of the Universities of Pittsburgh and California, San Diego, and the Center for Applied Genomics, Philadelphia. At the end of our project, we will have expanded our knowledge about pathogenesis of BA and related birth defects and identified candidate strategies to prevent or overcome delayed biliary morphogenesis. The international collaboration of leaders in hepatology (Kelly, Dhawan, Squires), transplant surgery (Sharif, Sindhi), genomics (Weeks, Hakonarson, Higgs), pathology (Ranganathan) and systems biology/bioinformatics (Subramanian, Higgs) is well suited to this task.

该项目将绘制胆道闭锁 (BA) 的疾病途径，该病所有治疗均无效，需要肝脏移植（LTx），以遗传易感性为共同基础，导致出生时的 BA 肝功能衰竭。占全世界儿童 LTx 的一半，但 BA 导致疤痕和疤痕的病因尚不清楚。闭锁胆管，无法排出肝脏。一些儿童的左右模式也异常。肝外器官单核苷酸多态性的初步全基因组关联研究（GWAS）。 BA 案例中的（SNP）以及来自人类 BA 和实验模型的其他证据使我们提出具体目标如下：目标 1. 我们将确认 BA 是否与 manosidase-1-α-2 中的 SNP 相关 (MAN1A2)，以及通过刺猬、表皮和转化生长因子发出信号的基因以及 BA 病例、敲除 man1a2 的斑马鱼和我们将通过对 Man1a2 -/-（敲除）小鼠进行靶向测序来识别潜在的新致病变异。目标 2. 我们将确认 man1a2 和其他候选基因的敲低是否会诱发胆汁。斑马鱼发育不全以及心脏和肝脏异位，离体小鼠气道纤毛发生受损纤毛发生的上皮模型，以及肝脏中上述发育途径的失调目标 3. 我们将利用这些重要的 SNP 位点构建 BA 的假定途径失调基因，在对目标 1 和 2 的数据进行综合系统分析时显示出相互作用。这些位点还将涉及异常的炎症和应激反应，我们将通过组合来证实途径。斑马鱼和前体中炎症和应激反应基因对发育基因的干扰我们期望异常的发育、炎症和应激反应信号传导。我们将对 800 名白人的最大同质队列进行基因分型。来自世界上三个最大儿科 LTx 中心的 LTx BA 病例：匹兹堡儿童医院、英国伦敦国王学院医院、英国伯明翰儿童医院我们将进行全基因组分析。我们将使用实验和方法对其中 80 个病例的肝脏样本进行转录组 (RNA) 测序。匹兹堡大学、加利福尼亚大学、圣地亚哥大学以及应用中心的生物信息学资源费城基因组学在我们的项目结束时，我们将扩展我们对疾病发病机制的了解。 BA 和相关的出生缺陷，并确定了预防或克服迟发性胆汁疾病的候选策略肝病学领域领导者（Kelly、Dhawan、Squires）的国际合作、移植外科（Sharif、Sindhi）、基因组学（Weeks、Hakonarson、Higgs）、病理学（Ranganathan）和系统生物学/生物信息学（萨勃拉曼尼亚，希格斯）非常适合这项任务。