Toward a CRISPR-AAV Gene Therapy Targeting a Mitochondrial Anchor to Treat Progressive Multiple Sclerosis

这个R21的前提是将Chiu实验室的啮齿动物工作转化为基因治疗， 进行性多发性硬化症（MS）。MS是年轻人神经系统残疾的主要脱髓鞘疾病 美国的成年人。MS开始于早期阶段，但转化为晚期或进行性阶段， 无法治愈从2015年到2019年，Chiu实验室确定了一种神经退行性疾病的特定机制， 通过研究两种不同小鼠模型（Shiverer和EAE/NOD）的进展期， 这是一种轴突特异性线粒体锚定蛋白 称为syntaphilin（SNPH），其在疾病过渡到晚期时过度上调。的 结果是线粒体沿着轴突沿着过度制动，破坏线粒体的再循环，导致 线粒体健康状况的恶化，最终杀死轴突。在过去的4年里，邱实验室 证明了两种进行性MS模型可以通过组成性SNPH-KO干预来挽救。 R21的目标是看看CRISPR-AAV基因疗法是否可以实现类似的拯救。我们有 设计了CRISPR分子剪刀来切割和沉默SNPH，并将剪刀包装成新型AAV 可以通过单剂量静脉注射穿透血脑屏障的载体。在目标#1中，我们将使用 CNS载体（AAV-PHP.eB）治疗Shiverer小鼠以拯救小脑。在目标#2中，我们将使用 PNS载体（AAV-PHP.S）治疗EAE/NOD小鼠以通过促进髓鞘再生来拯救脊髓。 结论-有许多FDA批准的药物用于MS的早期阶段，但没有有效的治疗方法， 一旦疾病发展到晚期，在过去的4年里，邱实验室已经确定了 线粒体的过度制动是使用两种啮齿动物在进行期杀死轴突的原因 模型这项R21赠款将把4年的啮齿动物工作转化为可能的基因疗法，以治疗人类 进行性MS

The premise of this R21 is to translate the rodent work in the Chiu laboratory to a gene therapy for progressive multiple sclerosis (MS). MS is the major demyelinating disease for neurological disability in young adults in the US. MS starts with an early phase but converts into a late or progressive phase that is currently incurable. From 2015-2019, the Chiu laboratory identified a specific mechanism for neurodegeneration in progressive MS by studying the progressive phase of two different mouse models (Shiverer and EAE/NOD) that mimic the complex range of human MS. The culprit is an axon-specific mitochondrial anchoring protein called syntaphilin (SNPH), which is excessively upregulated as the disease transitions into the late phase. The result is excessive braking of mitochondria along the axons that disrupts recycling of mitochondria, leading to degradation in mitochondrial health that ultimately kills the axons. In the last 4 years, the Chiu laboratory demonstrated that the two models of progressive MS can be rescued by constitutive SNPH-KO intervention. The goal of this R21 is to see if similar rescue can be achieved by CRISPR-AAV gene therapy. We have designed CRISPR molecular scissors to cut-and-silence SNPH and will package the scissors into novel AAV vectors that can penetrate the blood-brain-barrier by single-dose intravenous injections. In Aim #1, we will use a CNS vector (AAV-PHP.eB) to treat the Shiverer mouse to rescue the cerebellum. In Aim #2, we will use a PNS vector (AAV-PHP.S) to treat the EAE/NOD mouse to rescue the spinal cord by promoting remyelination. Conclusion – There are many FDA-approved drugs for the early phase of MS, but no effective treatments are available once the disease progresses into the late phase. In the last 4 years, the Chiu laboratory has identified excessive braking of mitochondria as a cause for killing axons in the progressive phase using two rodent models. This R21 grant will translate 4-years of rodent work into a possible gene therapy to treat human progressive MS.