ENZYME AND GENE THERAPY OF MPS I IN ANIMAL MODELS

MPS I 在动物模型中的酶和基因治疗

• 批准号: 6176442
• 负责人: ELIZABETH NEUFELD
• 金额: $ 36.33万
• 依托单位: UNIVERSITY OF CALIFORNIA LOS ANGELES
• 依托单位国家: 美国
• 财政年份: 1987
• 资助国家: 美国
• 起止时间: 1987-08-01 至 2003-07-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/6176442
• 关键词: O glycosidase; Retroviridae; behavior test; bone marrow transplantation; disease /disorder model; enzyme activity; enzyme therapy; gene therapy; genetic transduction; genetically modified animals; laboratory mouse; macrophage; mucopolysaccharidosis type I; nonhuman therapy evaluation; open field behavior; phenotype; recombinant proteins; transfection /expression vector

The molecular basis of Mucopolysaccharidosis I (MPS I, Hurler, Hurler/Scheie and Scheie syndromes) is mutations in the gene encoding alpha-L-iduronidase, resulting in absence of enzyme activity, accumulation of undegraded glycosaminoglycans, and systemic disease. Because alpha-L-iduronidase, a lysosomal enzyme, can be secreted as well as taken up by receptor-mediated endocytosis, MPS I has long been considered a prime candidate for replacement therapy. Alpha-L-Iduronidase provided by donor cells of hematopoietic origin (probably macrophages) is thought to be responsible for changes in disease progression that are seen after bone marrow transplantation. The course of the disease can also be altered by administration of recombinant alpha-L-iduronidase. The therapeutic effect of the enzyme previously observed in the canine MPS I model had been promising enough to generate a clinical trial in MPS I patients. But even though recombinant alpha-L-iduronidase may soon become available as a pharmaceutical, there is still a need for developing effective and long-lasting gene therapy. To have a suitable animal model, we have produced mutant mice by targeted disruption of the alpha-L-iduronidase gene. Aim 1 is to define the phenotype of the MPS I mouse model at the biochemical, pathological, behavioral and clinical levels. Aim 2 is to determine the effect of administration of human recombinant alpha-L-iduronidase on the disease phenotype, in order to provide a basis of comparison for gene-based procedures. Aim 3 is to compare transplantation of gene-modified bone marrow over-expressing human alpha-L-iduronidase with transplantation of bone marrow expressing normal levels of the enzyme, for effectiveness in altering the disease phenotype. Aim 4 is to determine the effectiveness of tetracycline-inducible alpha-L-iduronidase expression in macrophages as a means of enzyme delivery to affected organs, in particular to the brain, as well as to compare it with the above procedures for ability to alter the disease phenotype. The proposed studies represent steps in our long-term program to develop treatment for patients affected with MPS I.

粘多糖病I型(MPS I、Hurler、Hurler/Scheie和Scheie综合征)的分子基础是编码α-L艾杜糖醛酸酶基因突变，导致酶活性丧失、未降解的糖胺聚糖积累和全身性疾病。由于α-L-艾杜糖醛酸酶是一种溶酶体酶，可以通过受体介导的内吞作用进行分泌和摄取，因此MPS I长期以来一直被认为是替代治疗的首选方案。造血来源的供体细胞(可能是巨噬细胞)提供的α-L艾杜糖醛酸酶被认为与骨髓移植后疾病进展的变化有关。应用重组α-L艾杜糖醛酸酶也可改变病程。之前在犬MPS I模型中观察到的这种酶的治疗效果已经足够有希望在MPS I患者中产生临床试验。但是，即使重组的α-L艾杜糖醛酸酶可能很快就会成为一种药物，仍然需要开发有效和持久的基因疗法。为了有一个合适的动物模型，我们通过靶向破坏α-L艾杜糖酸酶基因产生了突变小鼠。目的1从生化、病理、行为学和临床水平确定MPS I小鼠模型的表型。目的2研究重组人α-L艾杜糖醛酸酶对疾病表型的影响，为基因治疗提供比较依据。目的3比较高表达人α-L艾杜糖醛酸酶基因修饰骨髓移植和正常表达该酶的骨髓移植对改变疾病表型的有效性。目的4是确定四环素诱导的α-L艾杜糖醛酸酶在巨噬细胞中的表达作为一种将酶输送到受影响的器官，特别是大脑的有效性，并将其与上述改变疾病表型的方法进行比较。拟议的研究代表了我们为受MPS I影响的患者开发治疗的长期计划的步骤。