Hematopoietic stem cell gene therapy for infantile neuronal ceroid lipofuscinosis

项目摘要/摘要 婴儿神经性蜡样脂褐素沉着症(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、最严重的神经元性类固醇之一 脂褐素增多症是一组常染色体隐性遗传性单基因溶酶体储存障碍 (LSD)发病率为1-8，全世界约100,000名活产儿中有1-8名。尽管付出了很大努力，但仍可获得 治疗仍然主要是对症治疗，实验方法无法减轻 患者体内PPT1缺失引起的毒性。PPT1活性不足以广泛传递到整个中枢神经系统 而且可能无法通过测试的策略成功地解决复杂的疾病发病机制 造成这一糟糕结果的原因。因此，我们提议的长期目标是开发一种创新的治疗方法 导致野生型PPT1广泛分布于整个中枢神经系统的INCL途径及防治 继发性疾病机制，有可能为受影响的患者带来全面而深远的好处。这 方法的基础是使用i)造血祖细胞(HSCs)作为组织渗透的来源 髓系后代细胞移植后能够将PPT1和其他治疗分子运送到中枢神经系统 在骨髓切除的受者中，ii)慢病毒载体(LV)允许有效地转移编码的cDNAs PPT1(和可能的其他治疗分子)进入HSC进行持续表达，III)创新 用于将经工程的造血干细胞输送到去髓移植的受者体内的方案，允许实现稳健和 移植细胞及其后代及时植入中枢神经系统和iv)交付，除 PPT1，是一种金属硫蛋白(MT)多肽，已知对包括继发性疾病机制有有利影响。我们的 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 而是长期、广泛和持续的PPT1功能来源，用于新陈代谢的挽救和塑造 NCLI患者脑和脊髓的神经保护环境。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。 在疾病动物模型以及体外和体内人类造血模型上的探讨，以及 确定疗效和临床益处的关键决定因素。到这个项目完成时，我们预计将产生一个 为未来INC儿童HSC基因治疗的临床试验奠定了基础。

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.