Pathogenic Mechanisms of Virus Induced Biliary Atresia

病毒性胆道闭锁的发病机制

• 批准号: 6961713
• 负责人: GREGORY M TIAO
• 金额: $ 12.58万
• 依托单位: CINCINNATI CHILDRENS HOSP MED CTR
• 依托单位国家: 美国
• 财政年份: 2005
• 资助国家: 美国
• 起止时间: 2005-09-15 至 2010-06-30
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/6961713
• 关键词: Reoviridae disease; Rotavirus; biliary atresia; biliary tract; cell line; chemokine; disease /disorder model; epithelium; flow cytometry; host organism interaction; inflammation; laboratory mouse; newborn animals; nuclear factor kappa beta; pathologic process; virus genetics; virus infection mechanism

DESCRIPTION (provided by applicant): Biliary atresia is the most common cause of neonatal cholestasis and if untreated results in end-stage liver disease (ESLD) and death. Even with current treatment strategies most children develop progressive liver disease and require liver transplantation for salvage. Biliary atresia is the number one indication for pediatric liver transplantation. Despite its importance, the pathogenesis of biliary atresia is unknown. One possible cause is an infection by an environmental agents such as viruses in a susceptible host. We established an experimental mouse model of biliary atresia and found that biliary injury in mice could be induced by a specific rotavirus species - rhesus rotavirus (RRV) in a susceptible murine host - BALB/c mice that progresses to ESLD and death. The inflammatory cholangiopathy is initiated at the biliary epithelial cell level and mirrors the disease process that is found in infants. This model will be used to define the molecular mechanisms regulating the interaction between a virus and the biliary system testing the over-arching hypothesis that the biliary atresia results from the abnormal recognition and infection of biliary epithelial cells (cholangiocytes) by a virus. This hypothesis will be addressed by the following specific aims: 1) Determine the specific RRV gene(s) necessary for the induction of biliary atresia in mice. 2) Determine the mechanism by which the cholangicoyte is susceptible to RRV infection. 3) Determine the mechanism by which RRV infected cholangiocytes triggers a host inflammatory response. The rotavirus property of gene reassortment will be used to identify the RRV gene(s) that cause the murine model of biliary atresia. A novel in vitro model in which RRV is able to infect a cholangiocyte cell line will be used to identify the mechanism by which RRV infects the cholangicoyte. Flow cytometry was used to detect the presence of the integrin apha2beta1 known to confer vulnerabiity to rotavirus infection. Blocking studies using natural ligands and monoclonal antibodies against this protein will be performed to determine its role. In vitro, cholangiocytes infected by RRV produce chemokines. This may be the triggering mechanism by which the host inflammatory response is initiated. We will determine if a similar process occurs in vivo. We will also determine if the NF-kappaB intracellular pathway is the mechansim by which RRV infection induces chemokine production.

描述（由申请人提供）： 胆道闭锁是新生儿胆汁淤积的最常见原因，如果未经治疗导致末期肝病（ESLD）和死亡。即使有了当前的治疗策略，大多数儿童都会发展为肝脏疾病，并需要肝移植以挽救。胆道闭锁是小儿肝移植的第一指示。尽管其重要性，但胆道闭锁的发病机理尚不清楚。一个可能的原因是易感宿主中的环境药物（例如病毒）感染。我们建立了胆道闭锁的实验小鼠模型，发现小鼠的胆道损伤可能是由特定的轮状病毒物种 - 易敏感的鼠宿主 - Balb/c小鼠造成的轮状病毒 - 轮状病毒（RRV），该小鼠发展为ESLD和ESLD和死亡。炎症性胆管疾病是在胆道上皮细胞水平上启动的，并反映了婴儿中发现的疾病过程。该模型将用于定义调节病毒与胆道系统之间相互作用的分子机制，以测试由病毒通过病毒的胆道上皮细胞（胆管细胞）的异常识别和感染引起的胆道闭锁的假设。该假设将通过以下特定目的来解决：1）确定小鼠胆道闭锁所必需的特定RRV基因。 2）确定胆管酯易受RRV感染的机制。 3）确定RRV感染的胆管细胞触发宿主炎症反应的机制。基因重新分类的轮状病毒特性将用于识别引起胆汁闭锁鼠模型的RRV基因。一种新型的体外模型，其中RRV能够感染胆管细胞细胞系将用于识别RRV感染胆管酯的机制。流式细胞仪用于检测已知的整联蛋白APHA2BETA1的存在，可将脆弱性赋予轮状病毒感染。将使用天然配体和针对该蛋白质的单克隆抗体进行阻断研究以确定其作用。在体外，由RRV感染的胆管细胞会产生趋化因子。这可能是启动宿主炎症反应的触发机制。我们将确定体内是否发生类似的过程。我们还将确定NF-kappab细胞内途径是否是RRV感染诱导趋化因子产生的机甲。