Innovative systemic gene therapy for treating Parkinson's disease

项目总结 帕金森氏病(PD)是一种日益普遍的神经系统疾病，目前影响约1 美国有100万人，全球有1000万人。尽管最近有创新，但最先进的 药物和手术治疗方案充其量仍是适度缓解和有症状。 基因治疗已经成为一种有希望的替代方法，可以阻止疾病的进展或潜在地 治愈疾病。然而，到目前为止，PD基因治疗的临床试验未能建立起一种 由于无法实现广泛和有效的基因转移而带来的有意义的治疗益处 大脑中的病区。正在进行的人体试验突显了这个问题的重要性， 其中，提高穿透性和转染率是首要目标。此外，缺乏可靠的 方法将基因治疗从血流部署到脑组织，迄今所有的临床研究都 采用高度侵入性的给药方式，包括将治疗直接注射到大脑中。这 现实排除了将早期PD患者纳入临床试验的可能性，这些患者更有可能对 心理治疗。因此，克服系统性基因传递的长期障碍的新方法 与PD相关的脑区，包括紧密封闭的血脑屏障(BBB)和致密的 脑细胞外基质(ECM)，是迫切需要的。为此，我们提出了创新的交付方法 开发：(I)临床可操作的MR图像引导聚焦超声(FUS)，以瞬时打开血脑屏障 基因治疗有针对性地渗透到脑组织和细胞中；(Ii)DNA负载 纳米颗粒具有一种独特的能力，可以有效地通过大脑ECM传播到并转染 大脑内病变区域的细胞(即DNA脑穿透纳米颗粒或DNA-BPN)，以及 (Iii)FUS介导的预适应，通过以下方式进一步增强DNA-BPN在脑内的分散 暂时降低ECM阻力。我们最近在我们的初步研究中表明，FUS介导的靶向BBB 我们的第一代DNA-BPN的渗透和随后广泛的基因转移导致了 传统的以神经毒素为基础的帕金森病临床前模型的治疗相关基因治疗。作为下一个 迈向临床翻译，我们在此建议进一步完善和评估我们的联合交付策略 在高度复杂和临床相关的家族性和散发性帕金森病临床前模型中，密切模仿 人类帕金森病的病理生理特征和疾病表型观察。如果成功，建议的 使用一种编码神经营养因子的基因(即目前 正在进行临床研究，并将在此处研究)，而其他临床前研究可能会随后进行测试 在这些先进的帕金森病模型中，新的遗传靶点的有效性。此外，该方法还可以 适用于以大脑内高度播散性疾病区域为特征的其他神经疾病。

PROJECT SUMMARY Parkinson's disease (PD) is an increasingly prevalent neurological disorder that currently affects about one million people in the United States and 10 million worldwide. Despite recent innovations, most advanced pharmacological and surgical therapeutic regimens remain moderately palliative and symptomatic at best. Gene therapy has emerged as an alternative promising means to halt the disease progression or potentially cure the disease. However, clinical trials of PD gene therapy up to this moment have failed to establish a meaningful therapeutic benefit due to an inability to achieve widespread and efficient gene transfer to the disease areas within the brain. The significance of this problem is highlighted by an ongoing human trial, wherein improving the penetration and efficiency of transfection is a primary goal. Further, lacking a reliable method to deploy gene therapy from the bloodstream to the brain tissue, all clinical studies to date have employed highly invasive administration modalities involving direct injection of the therapy into the brain. This reality has precluded the inclusion in clinical trials of early stage PD patients who are more likely to respond to the therapy. Thus, new methods to overcome long-standing barriers to systemic gene delivery throughout the PD-associated brain regions, including the tightly sealed blood-brain barrier (BBB) and the dense network of brain extracellular matrix (ECM), are sorely needed. To this end, we propose innovative delivery approaches exploiting: (i) clinically operable MR image-guided focused ultrasound (FUS) to transiently open the BBB for the penetration of gene therapy into the brain tissues and cells in a targeted manner, (ii) DNA-loaded nanoparticles possessing a unique capability to efficiently spread through the brain ECM to reach and transfect cells in the disease areas within the brain (i.e. DNA-loaded brain-penetrating nanoparticle or DNA-BPN), and (iii) FUS-mediated pre-conditioning that further enhances the dispersion of DNA-BPN within the brain by temporarily reducing ECM resistance. We recently showed in our pilot study that FUS-mediated, targeted BBB penetration of, and subsequent widespread gene transfer by, our first-generation DNA-BPN resulted in therapeutically relevant gene therapy of a conventional neurotoxin-based preclinical model of PD. As a next step towards clinical translation, we here propose to further refine and evaluate our combined delivery strategy in highly sophisticated and clinically-relevant preclinical models of familial and sporadic PD that closely mimic pathophysiological features and disease phenotypes observed in human PD. If successful, the proposed approach could be rapidly translated to the clinic using a gene-encoding a neurotrophic factor (that is currently under clinical investigation and will be studied here) while additional preclinical studies could be followed to test the effectiveness of novel genetic targets in these advanced PD models. In addition, the approach could also be applied to other neurological disorders characterized by highly disseminated disease areas within the brain.