GENE THERAPY FOR PHENYLKETONURIA

苯丙酮尿症的基因治疗

• 批准号: 6496717
• 负责人: PHILIP J LAIPIS
• 金额: $ 18.75万
• 依托单位: UNIVERSITY OF FLORIDA
• 依托单位国家: 美国
• 财政年份: 2001
• 资助国家: 美国
• 起止时间: 2001-08-01 至 2002-07-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/6496717
• 关键词: adeno associated virus group; disease /disorder model; gene therapy; laboratory mouse; liver cells; nonhuman therapy evaluation; phenylalanine 4 monooxygenase; phenylketonurias; recombinant virus; technology /technique development; transfection /expression vector

Phenylketonuria (PKU) is one of the most common genetic disorders affecting children in North America and Europe, with an incidence of about 1 in 10,000 births. Mutations in the enzyme phenylalanine hydroxylase (PAH) are the major cause of PKU. PAH deficiency results in elevated serum phenylalanine (Phe) levels, leading to abnormal brain development and mental retardation. PKU's frequency, coupled with the ability of early dietary modification to greatly reduce the severe neurological problems associated with the disorder, has led to neonatal testing programs in all states. Unfortunately, there is a widespread impression that dietary control effects a "cure" for this disease. In reality, strict adherence to the diet is exceedingly difficult and lapses can cause serious long-term neuro-development sequelae, particularly in offspring of PAH-deficient women. Given the well-understood single gene defect, gene therapy for PKU is both technically feasible and therapeutically desirable. Recent important advances in gene therapy have come from the use of AAV-based vectors to provide effective, stable, and safe correction of metabolic. It is hypothesized that AAV vectors will be useful in PKU. To this hypothesis, the ability of AAV vectors to: 1) Provide effective rescue of defective Phe metabolism in the Pah/enu2 mouse will be examined. Serum Phe levels will be related to the number of vector genomes and transfected cells as well as to the degree of reduction of PKU symptoms. 2) Give safe PAH delivery to liver with non germ-line transmission of vector sequences in either adult and neonatal Pah/enu2 mice will be tested. The potential for liver toxicity and immune responses to vector will also be examined. 3) Optimize PAH expression and hepatocyte delivery by using alternative control elements and tissue-specific targeting. These experiments provide a rational approach to examining the potential of AAV-driven gene therapy to truly cure PKU.

苯丙酮尿症（PKU）是影响北美和欧洲儿童的最常见遗传性疾病之一，发病率约为1/10，000。苯丙氨酸羟化酶（PAH）的突变是PKU的主要原因。PAH缺乏导致血清苯丙氨酸（Phe）水平升高，导致大脑发育异常和智力迟钝。PKU的频率，加上早期饮食调整的能力，大大减少了与疾病相关的严重神经系统问题，导致在所有国家的新生儿测试计划。不幸的是，人们普遍认为饮食控制可以“治愈”这种疾病。事实上，严格遵守饮食是非常困难的，失误可能会导致严重的长期神经发育后遗症，特别是在PAH缺乏女性的后代中。鉴于单基因缺陷已被充分理解，PKU的基因治疗在技术上是可行的，在治疗上是可取的。基因治疗的最新重要进展来自于使用基于AAV的载体来提供有效、稳定和安全的代谢校正。假设AAV载体将在PKU中有用。对于该假设，将检查AAV载体的以下能力：1）提供对Pah/enu 2小鼠中缺陷Phe代谢的有效拯救。血清Phe水平将与载体基因组和转染细胞的数量以及PKU症状的减轻程度相关。2)将在成年和新生Pah/enu 2小鼠中测试通过载体序列的非生殖系传播将PAH安全递送至肝脏。还将检查对载体的肝毒性和免疫反应的可能性。3)通过使用替代控制元件和组织特异性靶向，优化PAH表达和肝细胞递送。这些实验提供了一种合理的方法来检查AAV驱动的基因治疗真正治愈PKU的潜力。