The Molecular Determinants of Virus Induced Biliary Atresia

描述（由申请人提供）：胆道闭锁是儿科终末期肝病的最常见原因，也是儿科肝移植的头号适应症。由于在患病儿童的肝脏中发现了致病性病毒，因此胆道闭锁的病因学被认为是围产期病毒感染引发免疫介导的胆管上皮破坏。胆道闭锁的鼠模型支持病毒发病机制，因为感染恒河猴轮状病毒（RRV）的新生小鼠在门脉道内发展炎症和肝外胆管阻塞。RRV靶向胆管细胞进行感染，并且除了直接胆管细胞损伤之外，还诱导T细胞介导的对胆管上皮的损伤。 轮状病毒是由11个基因片段组成的dsRNA病毒。我们假设特定的轮状病毒基因控制感染胆管细胞和诱导免疫介导的损伤的能力。为了验证这一假设，我们从亲本菌株RRV和TUCH中产生了一套完整的单基因重组子。这些抑制剂为我们提供了一套独特的工具，以确定特定的轮状病毒基因如何促进发病机制。在初步研究中，我们发现RRV片段3，4，6，8，9和11是感兴趣的基因。考虑到对基因片段4的观察结果的稳健性，我们专注于该基因。我们将使用RRV -胆管细胞感染和T细胞活化的体外模型来确定基因片段4促成疾病发病机制的机制。我们还将利用反向遗传学产生突变基因片段4的感染性病毒，以确定在更复杂环境下的基础完整宿主。这些互补的方法将产生新的见解病毒引起的胆道闭锁。

DESCRIPTION (provided by applicant): Biliary atresia is the most common cause of pediatric end stage liver disease and the number one indication for pediatric liver transplantation. Because pathogenic viruses have been found in the liver of afflicted children, a proposed etiology for biliary atresia is a perinatal viral infection triggering immune mediated destruction of the biliary epithelium. The murine model of biliary atresia supports a viral pathogenesis as newborn mice infected with rhesus rotavirus (RRV) develop inflammation within the portal tract and extra- hepatic bile duct obstruction. RRV targets the cholangiocyte for infection and in addition to direct cholangiocyte injury also induces T-cell mediated injury to the biliary epithelium. Rotavirus is a dsRNA virus comprised of 11 gene segments. We hypothesized that specific rotavirus genes govern the ability to infect the cholangiocyte and induce immune mediated injury. To test this hypothesis, we generated a complete set of single gene reassortants derived from the parental strains RRV and TUCH. These reassortants give us a unique set of tools to determine how specific rotavirus genes contribute to the pathogenesis. In preliminary studies, we found that RRV segments 3, 4, 6, 8, 9 and 11 are genes of interest. Given the robust nature of the observations made with gene segment 4, we focused on this gene. We will use in vitro models of RRV - cholangiocyte infection and T-cell activation to determine the mechanisms by which gene segment 4 contributes to disease pathogenesis. We will also use reverse genetics to generate mutate gene segment 4 infectious virus to determine the basis in the more complex environment of the intact host. These complimentary approaches will generate new insight in viral induced biliary atresia.