RNAi for the Treatment of Viral Hepatitis

描述（由申请人提供）：这项工作的目标是推进我们的原始研究，以发展基于rnai的临床治疗所需的科学原理。我们的计划是提供一个安全有效的基于转录的RNA干扰（RNAi）进入肝脏等重要器官的平台。我们特别感兴趣的是开发一种治疗丙型肝炎病毒感染（HCV）的方法，这仍然是一个未满足的临床需求。直到最近，由于缺乏研究细胞培养中完整病毒感染的复制能力和缺乏动物模型，这一领域的研究一直受到阻碍。因此，HCV复制子一直是研究病毒复制的主要手段。我们已经发现，一些RNAi靶标对复制子有效，但对具有相同靶标序列的真正病毒感染相对惰性。我们计划基于我们的新模型和shrna载体生物学的信息，重新评估HCV基因组的各个区域的RNAi敲除。此外，我们将尝试明确评估靶向HCV负链的有效性，因为它在感染细胞中产生的量要少得多。我们将确定是否同时针对两条链将提供更好的保护和减少准物种形成的可能性。我们计划用我们新开发的重组AAV载体进行细胞培养和人源化小鼠肝脏模型，并确定RNAi作为HCV暴露保护手段的有效性，以及在建立持续感染后消除病毒的有效性。在批准期结束时，我们相信我们将能够为有效的基于载体的RNAi在体内所需的参数提供重要的见解，并拥有一个强大的临床相关治疗HCV感染的方法，作为单一疗法和/或与其他非核酸疗法联合使用。

DESCRIPTION (provided by applicant): The goal of the work is to advance our original studies on developing the scientific principles required for RNAi-based clinical therapeutics. Our plan is to provide a platform for safe and effective transcription-based RNA interference (RNAi) into vital organs such as the liver. We are specifically interested in developing a therapeutic approach for Hepatitis C Virus Infection (HCV) for which there is still an unmet clinical need. Until recently, research in this area has been hampered by the lack of ability to study replication from an intact viral infection in cell culture and the paucity of animal models. As a result, HCV replicons have been the primary means to study viral replication. We have discovered that some RNAi targets are effective against replicons but relatively inert against bona-fide viral infection that shares identical target sequences. We plan to re-evaluate various regions of the HCV genome for RNAi knockdown based on our new models and information regarding shRNA-vector biology. In addition, we will attempt to definitively evaluate the effectiveness of targeting the HCV minus strand because it is produced in much lower amounts in infected cells. We will determine if targeting both strands simultaneously will provide better protection and lessen the likelihood of quasi-species formation. We plan to use cell culture and humanized mouse liver models with our newly developed recombinant AAV vectors and determine the validity of RNAi as a means to protect against HCV exposure as well as elimination of the virus after establishment of a sustained infection. By the end of the granting period, we believe we will be able to provide important insights into the parameters required for effective vector-based RNAi in vivo and have a robust clinically relevant means of treating HCV infection as a single therapy and/or in combination with other non-nucleic acid based therapeutics. PUBLIC HEALTH RELEVANCE: The goal of this work is to develop the scientific principles and pave the way to develop a safe and efficacious clinical therapy for Hepatitis C virus infection using RNA interference (RNAi). RNAi is a powerful new technology for turning off unwanted genes such as those present in a viral pathogen. The new anti-HCV RNAI therapeutics will be tested for their ability to eliminate and/or prevent HCV infection in newer clinically relevant cell culture and rodent models of HCV infection.