Hematopoietic stem cell gene therapy for infantile neuronal ceroid lipofuscinosis

项目总结/摘要 婴儿神经元蜡样质脂褐质沉积症（INCL），由编码棕榈酰的CLN1基因缺陷引起 蛋白硫酯酶-1（PPT1）是进展最快和最严重的神经元蜡样变之一 脂褐质沉积症是一组常染色体Recombinant遗传的单基因溶酶体沉积症， （LSD），全世界约100，000例活产中有1 - 8例发生。尽管付出了巨大的努力， 治疗仍然主要是对症治疗，实验方法无法减轻 患者中PPT1缺失引起的毒性。PPT1活性向整个CNS的广泛传递不足 以及无法通过测试的策略成功解决复杂的疾病发病机制是可能的 这一糟糕结果的原因。因此，我们提案的长期目标是开发一种创新的治疗方法， INCL的方法导致野生型PPT1在整个CNS中广泛生物分布， 继发性疾病机制，对受影响的患者有潜在的整体深远的好处。这 该方法基于使用i）造血和祖细胞（HSC）作为组织浸润的来源， 能够在移植时将PPT 1和其它治疗分子递送至CNS的骨髓后代细胞 在骨髓清除的接受者中，ii）允许有效转移编码 用于PPT 1（和可能的其他治疗分子）进入HSC以持续表达，iii）创新的 用于将工程化的HSC递送到骨髓清除的受体中的方案允许实现稳健的且 移植细胞及其后代在CNS中的及时植入，以及iv）递送， 金属硫蛋白（MT）肽的PPT1，已知对INCL继发性疾病机制产生有利影响。我们 中心假设是，利用这些成分的HSC基因治疗方法可以产生快速的 但长期持久，广泛和持续的来源的功能性PPT 1的代谢救援和形状， NCLI患者的大脑和脊髓中的神经保护环境。预计这将与 对疾病的影响因此，在拟议的项目中，我们将挑战这种方法的有效性、可行性和安全性。 在疾病动物模型中的方法，以及在人体造血的体外和体内模型中的方法，以及 确定疗效和临床获益的关键决定因素。通过完成这个项目，我们预计将产生一个 为将来在INCL儿童中进行HSC基因治疗的临床试验奠定了坚实的基础。

PROJECT SUMMARY/ABSTRACT Infantile neuronal ceroid lipofuscinosis (INCL), caused by defects in the CLN1 gene coding for palmitoyl protein-thioesterase-1 (PPT1), is the most rapidly progressing and one of the most severe neuronal ceroid lipofuscinoses, which are a group of autosomal recessively inherited monogenic lysosomal storage disorders (LSDs) with an incidence of 1-8 in about 100,000 live births worldwide. Despite great efforts, available treatments remain mainly symptomatic and experimental approaches are unable to relieve the burden of toxicity caused by loss of PPT1 in patients. Insufficient widespread delivery of PPT1 activity to the entire CNS and inability to successfully address the complex disease pathogenesis by the tested strategies are likely reasons for this poor outcome. Thus, the long–term goal of our proposal is to develop an innovative therapeutic approach for INCL leading to widespread biodistribution of wild type PPT1 to the entire CNS and control of secondary disease mechanisms, with potential for an overall profound benefit for affected patients. This approach is based on the use of i) hematopoietic and progenitor cells (HSCs) as source of a tissue infiltrating myeloid progeny cells able to delivery PPT1 and other therapeutic molecules to the CNS upon transplantation in myeloablated recipients, ii) lentiviral vectors (LVs) allowing for an efficacious transfer of the cDNA encoding for PPT1 (and possibly other therapeutic molecules) into HSCs for sustained expression, iii) innovative protocols for the delivery of the engineered HSCs into myeloablated recipients allowing to achieve a robust and timely engraftment of the transplanted cells and their progeny in the CNS and iv) the delivery, in addition to PPT1, of a metallothionein (MT) peptide known to favorably impact INCL secondary disease mechanisms. Our central hypothesis is that a HSC gene therapy approach exploiting these components could generate a rapid but long-lasting, widespread and sustained source of the functional PPT1 for metabolic rescue and shape a neuro-protective environment in the brain and spinal cord of NCLI patients. This is expected to have relevant impact on the disease. In the proposed project we will thus challenge the efficacy, feasibility and safety of this approach in the disease animal model, as well as on in vitro and in vivo models of human hematopoiesis, and identify key determinants of efficacy and clinical benefit. By completion of this project, we expect to generate a solid basis for future clinical testing of HSC gene therapy in INCL children.