Biological Basis of Phenotypes and Clinical Outcomes in Biliary Atresia

描述(由申请人提供)：这是一份竞争性的续签申请，建议对NIDDK-儿童肝病研究和教育网络(儿童)进行辅助研究。胆道闭锁是新生儿胆汁淤积最常见的原因，由肝外胆管纤维炎性阻塞引起。尽管进展几乎一致到终末期肝硬变，但对外科/内科治疗的不同反应和疾病的进展速度表明，存在未被识别的生物学过程，这些过程正在驱动不同的表型或疾病阶段。在该奖项的第一个任期内，我们发现了树突状细胞和自然杀伤细胞在疾病发病机制中的证据，确定了ADD3基因在疾病易感性中的作用，并产生了肝脏疾病炎症和纤维化阶段的基因表达特征，即使使用标准的组织学标准，这些阶段也与临床结果有关。在这一应用的发现型初步研究中，我们量化了血清中的炎症生物标记物，并确定了对胆道闭锁具有高度特异性并预测对手术治疗的充分反应的蛋白质图谱。这些数据构成了总体假设的基础，即与胆道损伤发病机制相关的肝脏和循环生物标志物是诊断、肝脏疾病分期和临床结果的预测因子。为了检验这一假设，我们 将创建一个数据集成平台，将关键的临床、实验室和组织数据与胆道闭锁患者和疾病-以及健康对照的基因(在肝脏中)和蛋白质(在血清中)的全面表达谱结合在一起。我们将挖掘该平台以实现三个目标：1)根据临床结果确定胆道闭锁诊断时的疾病阶段，2)确定生物学预测因素和对治疗的有利反应，3)发现组织纤维化和临床终点的血清生物标志物。AIM 1的实验将使用RNAseq生成全基因组表达数据集，以验证炎症和纤维化特征，并在诊断时对肝病进行分期，识别对类固醇治疗反应的分子预测因子，并研究疾病的新转录机制。AIMS 2和AIMS 3的实验将使用蛋白质复合技术来量化炎症和纤维化的血清生物标记物，并使用高度严格的统计模型来根据患者的生物组成(疾病阶段)来定义以前未识别的患者亚组，这些亚组可以预测对标准手术、新药物治疗和门静脉高压症进展的反应。通过应用高度互补的方法来研究来自足够大小的队列的组织，这些组织已经被儿童预期的表型，我们的实验将提供关于如何根据疾病的生物标记物对未来的临床试验和受影响儿童的护理进行个性化的洞察。

DESCRIPTION (provided by applicant): This is a competing renewal application proposing ancillary studies to the NIDDK-Childhood Liver Disease Research and Education Network (ChiLDREN). Biliary atresia, the most common cause of neonatal cholestasis, results from a fibro-inflammatory obstruction of extrahepatic bile ducts. 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 first tenure of the award, we found evidence for dendritic and natural killer cells in pathogenic mechanisms of disease, identified a role for the ADD3 gene in susceptibility of disease, and generated a gene expression signature of inflammatory and fibrotic stages of liver disease at presentation, which have relationship to clinical outcome even when these stages are not present using standard histological criteria. In discovery-type preliminary studies for this application, we quantified inflammatory biomarkers in the serum and identified protein profiles that are highly specific for biliary atresia and predict adequate response to surgical treatment. These data form the foundation for the overall hypothesis that hepatic and circulating biomarkers linked to pathogenesis of biliary injury are predictors of diagnosis, stages of liver disease, and clinical outcome. To test this hypothesis, we will create a Data Integration Platform with key clinical, laboratory and histological data combined with comprehensive expression profiles for genes (in the liver) and protein (in the serum) of patients with biliary atresia and diseased- and healthy-controls. We will mine the platform to pursue three aims: 1) To define disease stages at diagnosis of biliary atresia with relevance to clinical outcome, 2) To identify biological predictors and favorable response to treatment, and 3) To discover serum biomarkers of tissue fibrosis and clinical end-points of cirrhosis. Experiments for Aim 1 will use RNAseq to generate whole-genome expression datasets to validate inflammatory and fibrotic signatures and stage the liver disease at diagnosis, identify molecular predictors of response to steroid treatment, and investigate new transcriptional mechanisms of disease. Experiments for Aims 2 and 3 will use protein-multiplexing technologies to quantify serum biomarkers of inflammation and fibrosis and highly stringent statistical models to define previously unrecognized subgroups of patients based on their biological makeup (stages of disease) that are predictive of response to standard surgery, new medical therapies, and progression of portal hypertension. By applying highly complementary approaches to study tissues from adequately sized cohorts that have been prospectively phenotyped by ChiLDREN, our experiments will provide insight into how future clinical trials and the care of affected children can be personalized based on biomarkers of disease.