TESTING INFECTIVITY OF HCV ISOLATED FROM CELL CULTURE IN CHIMPANZEES

这个子项目是利用由NIH/NCRR资助的中心拨款提供的资源的许多研究子项目之一。子项目和调查员(PI)可能从另一个NIH来源获得了主要资金，因此可能会出现在其他CRISE条目中。列出的机构是针对中心的，而不一定是针对调查员的机构。在接触过丙型肝炎病毒的人中，大约85%的人会慢性感染丙型肝炎病毒。目前，美国估计有270万慢性感染者，全球估计有2亿人。目前还没有疫苗，慢性丙型肝炎病毒感染的治疗仅限于干扰素和利巴韦林的组合，但治疗成功的患者不到一半。目前存在着较差的病毒细胞培养系统，尚未证明在实验室之间是可复制的，唯一的病毒动物模型是黑猩猩。最近，我们成功地在细胞培养中产生了传染性丙型肝炎病毒(简称HCVcc)。这项黑猩猩实验的目标是测试这些颗粒在体内的传染性。对于大多数丙型肝炎病毒分离株，适应性突变是细胞培养中有效复制RNA所必需的。虽然只有有限数量的这些适应性变化在体内进行了测试，但它们似乎对黑猩猩的复制有害，而且很少在天然丙型肝炎病毒分离株的序列中检测到。在黑猩猩体内测试这种分离株或细胞培养的感染性嵌合体对丙型肝炎病毒领域具有潜在的重要意义。直到这一点，体内产生的丙型肝炎病毒(从黑猩猩或人类)在细胞培养中是非传染性的或传染性很弱的。相反，适应于在细胞培养中复制的丙型肝炎病毒RNA在体内复制的能力受到损害。拥有一种既能在细胞培养中复制又能在体内复制的分离株将是表征丙型肝炎病毒复制、进入和发病机制的一个非常强大的工具。这将使我们能够将肝脏中产生的真实丙型肝炎病毒颗粒的行为与细胞培养中产生的HCVcc进行比较。这将对病毒进入和中和的研究特别重要，并减少对未来黑猩猩实验的需求。将两种不同细胞培养适应病毒的10^6细胞培养感染单位静脉接种。变成了两种不同的动物。(总体积~1-2毫升)。接种物将由浓缩的细胞培养上清液组成。动物每周都会被放血，并监测丙型肝炎病毒血症。如果8周后没有发现感染迹象，动物将被一种已知的传染性分离株(HCVH77单克隆病毒)攻击，以证明其传染性。

This subproject is one of many research subprojects utilizing the resources provided by a Center grant funded by NIH/NCRR. The subproject and investigator (PI) may have received primary funding from another NIH source, and thus could be represented in other CRISP entries. The institution listed is for the Center, which is not necessarily the institution for the investigator. Hepatitis C virus infections in man become chronic in approximately 85% percent of individuals exposed. At present there are an estimated 2.7 million chronically infected people in the United States and an estimated 200 million worldwide. There is no vaccine and therapy for chronic HCV infections is limited a combination of interferon and ribavirin, but treatment is successful in less than half the patients. There currently exist poor cell culture systems for the virus which have not proved to be reproducible between labs and the only animal model for the virus is the chimpanzee. Recently we succeeded in producing infectious hepatitis C virus in cell culture (termed HCVcc). The goal of this chimpanzee experiment is to test the infectivity of these particles in vivo. For most HCV isolates, adaptive mutations are required for efficient RNA replication in cell culture. Although only a limited number of these adaptive changes have been tested in vivo, they appear to be deleterious for replication in chimpanzees and have only rarely been detected in sequences of natural HCV isolates. Testing this isolate or cell culture infectious chimeras in chimpanzees is potentially of great importance to the HCV field. Until this point, HCV produced in vivo (from chimpanzees or humans) is non-infectious or poorly infectious in cell culture. Conversely, HCV RNAs adapted to replicate in cell culture are compromised in their ability to replicate in vivo. Having an isolate that can replicate both in cell culture and in vivo would be a very powerful tool for characterizing HCV replication, entry and pathogenesis. This will enable us to compare the behavior of true HCV particles produced in the liver to HCVcc produced in cell culture. The will be particularly important for studies of virus entry and neutralization and also reduce the need for future chimpanzee experiments. 10^6 cell culture infectious units of two different cell culture adapted viruses will be inoculated i.v. into two different animals. (Total volume ~1-2mL). The inoculum will consist of concentrated cell culture supernatant. Animals will be bled weekly and monitored for HCV viremia. If no infection is indicated after 8 weeks the animals will be challenged with a known infectious isolate (HCVH77 monoclonal virus) to demonstrate infectivity.