Biological Basis of Phenotypes and Clinical Outcomes in Biliary Atresia

项目总结/摘要 这是一个竞争性的更新应用程序，研究临床表型的生物学基础和 胆道闭锁，新生儿胆汁淤积症的最常见原因。这种疾病是由纤维炎症引起的， 肝外胆管阻塞，出现在婴儿早期。尽管几乎一致的进展到最后- 阶段肝硬化，对手术/药物治疗的可变反应和疾病进展速度表明 存在未被识别的生物过程，这些生物过程驱动疾病的不同表型或阶段。 在该奖项的上一个任期内，我们发现了通过IL-8，TNF和组分增加信号的证据。 炎症小体在胆管损伤发病机制中的作用，以及分子回路的同时激活 依赖IL-33诱导组织修复。我们还确定了MMP-7在胆管上皮损伤中的关键作用 并且作为胆道闭锁的高度敏感和特异的生物标志物。在准备此应用程序时，我们 应用计算机建模和高级分析来挖掘肝脏转录组，发现了一个14个基因， 一个可以预测自体肝脏2年生存率的信号，并将谷胱甘肽代谢确定为一种新的 治疗靶点来抑制纤维化。利用血清蛋白质组学，我们还发现了 与门静脉高压症确定的晚期纤维化儿童隔离。这些数据构成了 新研究的基础提出了三个相互关联的目标：1）发现分子决定因素， 胆道闭锁的结果和发病机制，2）确定门静脉高压症的生物标志物， 肝脏疾病的进展; 3）明确胆道闭锁组织损伤的致病机制。 Aim 1的实验将使用来自大型队列的RNAseq数据来挖掘基因组和分子通路 预测临床结果，随后在胆道闭锁的小鼠模型中进行补充研究， 在临床前试验中，通过靶向肝脏中的代谢回路来抑制纤维化。实验 目的2将使用血清蛋白质组学的数据来研究SEMA 6 B，sFRP 3，COMMD 7，VCAM 1和BMX如何在体内表达。 作为门静脉高压症的生物标志物单独或组合。目标3的实验将 从患有胆道闭锁的受试者的肝脏中获得胆道类器官，并检验与 细胞成熟和如何激活胆管细胞的纤维化是胆汁分泌的重要机制 导管损伤通过应用高度互补的方法来研究来自适当规模的队列的组织， 已经进行了前瞻性的表型分型，我们的实验将提供对疾病的新生物标志物， 在发病机制中的作用，以及如何根据生物学终点对新的临床试验进行个性化。

PROJECT SUMMARY/ABSTRACT This is a competing renewal application studying the biological basis of clinical phenotype and outcome of biliary atresia, the most common cause of neonatal cholestasis. The disease results from a fibro-inflammatory obstruction of extrahepatic bile ducts and present in early infancy. Despite nearly uniform progression to end- stage cirrhosis, the variable response to surgical/medical treatment and rate of progression of disease suggest the existence of unrecognized biological processes that are driving different phenotypes or stages of disease. In the previous tenure of the award, we found evidence of increased signaling via IL-8, TNF, and components of the inflammasome in pathogenesis of bile duct injury, and the simultaneous activation of molecular circuits dependent on IL-33 to induce tissue repair. We also identified a key role for MMP-7 in bile duct epithelial injury and as a highly sensitive and specific biomarker for biliary atresia. In preparation for this application, we applied computer modeling and high analytics to mine the hepatic transcriptome and found a 14-gene signature that predicts 2-year survival with the native liver and identifies glutathione metabolism as a new therapeutic target to suppress fibrosis. Using serum proteomics, we also uncovered serum proteins that segregate with children with advanced fibrosis as determined by portal hypertension. These data form the foundation for the new studies proposed in three inter-related aims: 1) To discover molecular determinants of outcome and pathogenesis of biliary atresia, 2) To identify biomarkers of portal hypertension during progression of liver disease, and 3) To define pathogenic mechanisms of tissue injury in biliary atresia. Experiments for Aim 1 will use RNAseq data from a large cohort to mine gene groups and molecular pathways that predict clinical outcome, followed by complementary studies in mouse models of biliary atresia and neonatal fibrosis in pre-clinical trials to suppress fibrosis by targeting metabolic circuits in the liver. Experiments for Aim 2 will use data from serum proteomics to investigate how SEMA6B, sFRP3, COMMD7, VCAM1, and BMX perform as biomarkers of portal hypertension individually or in combination. And experiments in Aim 3 will derive biliary organoids from the liver of subjects with biliary atresia and test hypothesis related to defects of cell maturation and to how the activation of fibrogenesis in cholangiocytes is an important mechanisms of bile duct injury. By applying highly complementary approaches to study tissues from adequately sized cohorts that have been phenotyped prospectively, our experiments will provide insight into new biomarkers of disease, their role in pathogenesis, and how new clinical trials can be personalized based on biological end-point.