Novel AAVs engineered for efficient and noninvasive cross-species gene editing throughout the central nervous system

项目总结： 由于缺乏有效的治疗方法，许多影响中枢神经系统(CNS)的遗传性疾病仍无法治愈 小分子药物或生物制品。利用体细胞基因靶向这些疾病的遗传基础 因此，编辑将特别有影响力，但它的成功实施将需要安全的方法 并高效地在整个中枢神经系统中传递基因和基因编辑机制。自动对讲机是最先进的 体内基因转移的载体，因为它们可以提供安全和持久的体内基因表达。自动增值服务 是唯一被监管机构批准直接用于人类的基因治疗载体 美国和欧洲的代理机构。此外，在2017年，自动驾驶飞机成为第一辆作为早期 评估体内基因编辑安全性的阶段临床试验。尽管他们令人印象深刻的临床前和临床 安全记录，到目前为止测试的自然产生的AAV缺乏在大多数情况下进行基因传递所需的效率 器官系统，包括中枢神经系统。为了满足对更好的中枢神经系统基因传递工具的需求，我们最近 使用定向进化和一种新的细胞类型特异性体内选择方法来设计几种新型的AAVs， 最值得注意的是AAV-PHP.B和AAV-PHP.eB，它们首次使非侵入性 将基因转移到成年小鼠中枢神经系统中的大多数神经元和星形胶质细胞。在这里，我们的目标是建立 在这种选择方法成功后，通过设计能够在整个过程中实现高效基因转移的AAVs 包括非人灵长类在内的多种物种的中枢神经系统。我们开发的AAV将在几个方面进行评估 在神经元中提供全中枢神经系统转基因表达和定向基因组编辑的能力，以及 改进的AAV变种将与科学界共享。本项目圆满完成， 涉及将新的AAVs与下一代基因编辑技术配对，将为评估 人体试验中中枢神经系统基因编辑的安全性。

Project Summary: Many genetic diseases that affect the central nervous system (CNS) remain untreatable due to a lack effective small molecule drugs or biologics. Targeting the genetic underpinnings of these diseases with somatic cell gene editing would therefore be particularly impactful, but its successful implementation will require methods to safely and efficiently deliver genes and gene editing machinery throughout the CNS. AAVs are the state-of-the-art vehicles for in vivo gene transfer because they can provide safe and long lasting in vivo gene expression. AAVs are the only gene therapy vectors that have been approved for direct administration to humans by regulatory agencies in both the US and Europe. Moreover, in 2017, AAVs became the first vehicle used as part of an early phase clinical trial to evaluate the safety of in vivo gene editing. Despite their impressive preclinical and clinical safety record, naturally occurring AAVs tested to date lack the efficiency required for gene delivery across most organ systems, including the CNS. To address the need for better vehicles for CNS gene delivery, we recently used directed evolution and a new cell type-specific in vivo selection method to engineer several novel AAVs, most notably AAV-PHP.B and AAV-PHP.eB, that have, for the first time, made it possible to noninvasively transfer genes to the majority of neurons and astrocytes throughout the adult mouse CNS. Here, we aim to build upon the success of this selection approach by engineering AAVs that enable efficient gene transfer throughout the CNS of multiple species, including nonhuman primates. The AAVs we develop will be evaluated in several species for their ability to provide CNS-wide transgene expression and targeted genome editing in neurons, and improved AAV variants will be shared with the scientific community. Successful completion of this project, which involves pairing the new AAVs with next-generation gene editing technologies, will provide support for evaluating the safety of CNS gene editing in human trials.