In Vivo Hematopoietic Stem Cell Gene Therapy of Beta-Thalassemia and Sickle Cell Disease

摘要： 造血干细胞（HSC）基因治疗可以为许多血液病提供治愈性治疗。 传统的方法是基于离体HSC基因转移，并取得了令人鼓舞的结果。 然而，高成本和副作用限制了离体HSC基因治疗的患者可及性。我们有 开发了一种涉及HSC动员和静脉内病毒载体的体内HSC转导方法 注射该方法的特点是成本相对较低，技术简单。它可以被提供为 门诊治疗我们已经在几种鼠疾病模型中证明了其安全性和有效性， 包括β-地中海贫血、镰状细胞贫血和血友病A，以及最近在恒河猴中的研究。与 随着越来越多的基因治疗产品的出现，体内HSC转导的应用可以外推基因治疗， 为更多的患者群体提供治疗。进一步改进体内HSC基因治疗， 临床应用包括更有效的动员方案，完全消除先天性反应， 静脉内载体注射，更先进的病毒衣壳修饰，其避开预先存在的抗载体 免疫力、改进的体内选择方案以及用于纯化基因转移载体的新方法。 在本申请中，我们将连续测试假设，以改善体内HSC基因治疗方法， 地中海贫血和镰状细胞病小鼠模型。然后，我们将验证以下各项的最佳组合 在非人类灵长类动物身上的进步安全性、有效性、便携性和低成本是 每个技术单元的设计/优化。

Abstract: Hematopoietic stem cell (HSC) gene therapy could provide a curative treatment for a number of blood diseases. The conventional approach is based on ex vivo HSC gene transfer and has achieved encouraging results. However, the high cost and side effects limit the patient accessibility of ex vivo HSC gene therapy. We have developed an in vivo HSC transduction approach involving HSC mobilization and intravenous viral vector injection. The approach is highlighted by its relatively low cost and technical simplicity. It could be provided as an outpatient treatment. We have demonstrated its safety and efficacy in several murine disease models, including β-thalassemia, Sickle Cell Anemia, and hemophilia A, and more recently, in rhesus macaques. With more gene therapy products on the horizon, the application of in vivo HSC transduction could extrapolate genetic treatments to a larger patient population. Further improvements of in vivo HSC gene therapy on the road to clinical application include more effective mobilization protocols, complete elimination of innate responses upon intravenous vector injection, more advanced virus capsid modifications that circumvent pre-existing anti-vector immunity, improved in vivo selection regimens, as well as new methods for purification of gene transfer vectors. In this application, we will successively test hypotheses to improve in vivo HSC gene therapy approaches for thalassemia and Sickle Cell Disease in mouse models. We will then validate the best combination of improvements in hon-human primates. Safety, efficacy, portability, and low costs are the major driving forces in the design/optimization of each technological unit.