Overcoming our clinical complications: AAV vector design for the treatment of DMD

克服临床并发症：治疗 DMD 的 AAV 载体设计

基本信息

批准号：
8925675
负责人：
Matthew Louis Hirsch
金额：
$ 32.04万
依托单位：
UNIV OF NORTH CAROLINA CHAPEL HILL
依托单位国家：
美国
项目类别：
财政年份：
2013
资助国家：
美国
起止时间：
2013-09-17 至 2016-08-31
项目状态：
已结题

来源：
https://reporter.nih.gov/project-details/8925675
关键词：
Adverse effects Aftercare Animal Model Antigen Presentation Antigens Attenuated Canis familiaris Cells Clinical Clinical Trials Communities Complementary DNA Development Disease Duchenne muscular dystrophy Dystrophin Engineering Ensure Fiber Gene Expression Gene Transduction Agent Gene Transfer Genes Goals Hereditary Disease Human Human Virus Immune Immune response Immune system Immunosuppression Immunosuppressive Agents Injection of therapeutic agent Lymphocyte Mediating Modeling Muscle Muscle Fibers Muscle function Mutation Nature Outcome Study Pathogenesis Patients Peptides Pharmaceutical Preparations Phase Proteins Reagent Regulatory T-Lymphocyte Skeletal Muscle Solutions Surface T cell response T-Lymphocyte Techniques Testing Therapeutic Transgenes Tropism Variant Viral Viral Genes Viral Proteins Virion Virus Wit adeno-associated viral vector cellular transduction cytotoxic gene therapy genetically modified cells improved killings mdx mouse meetings mini-dystrophin muscle degeneration mutant novel strategies novel therapeutic intervention preclinical study prevent public health relevance research study response therapeutic gene therapy design vector vector genome

项目摘要

DESCRIPTION (provided by applicant): Our recent clinical trial using adeno-associated viral vectors (AAV) to deliver Mini-Dystrophin to the muscle of patients with Duchenne muscular dystrophy (DMD) was met with an unexpected result; after treatment, a Dystrophin-specific T-cell response was found in two patients, which was related to revertant fiber development prior to therapy. These Dystrophin-specific T cells have the potential to eradicate all genetically modified muscle resulting in an ineffective therapy, as well as presenting a general concern for gene therapy communities in general. Currently, no strategy exists to avoid transgene-specific CTLs, whether they are pre-existing or therapy- induced, and systemic long-term immunosuppression is considered a non-viable option. However, particular viruses found in nature have evolved a potential solution to this dilemma by synthesizing small peptides that inhibit antigen presentation only in transduced cells. In preliminary experiments, we demonstrate that the cellular synthesis of these viral inhibitory peptides (termed VIPRs) prevents the surface presentation of a well-defined antigen, thus protecting transduced cells from the host's immune response. In the current proposal, we will use a canine DMD model (GRMD) to evaluate the evasion ability of VIPRs from Dystrophin- specific CTL-mediated elimination of AAV transduced muscles. First, we will test whether the utilization of VIPRs can block the induction of a Dystrophin-specific CTL response after AAV muscle injection (Aim 1). Next, we will study whether the application of VIPRs will help AAV transduced muscle fibers escape pre-existing Dystrophin-specific CTL-mediated elimination (Aim 2). To decrease the vector cassette size for efficient virion package and/or to enhance the evasion ability of VIPRs, we will optimize the VIPR domains and test the immune evasion capacity of mutant variants (Aim 3). By delivering VIPRs and mini-dystrophin in the same vector, this approach ensures that antigen presentation will be attenuated only in AAV- transduced cells without systemic side effects on the immune system (as would be the case using immunosuppressive drugs or by the application of regulatory T-cells). Collectively, this proposal outlines a promising strategy to overcome our clinical DMD observations and concerns for gene therapy studies in general, by creating an AAV vector capable of avoiding the host's immune response to a foreign protein.

描述（由申请人提供）：我们最近使用腺相关病毒载体（AAV）向Duchenne肌肉营养不良（DMD）患者的肌肉提供迷你肺炎蛋白（DMD）的临床试验。治疗后，在两名患者中发现了肌营养不良蛋白特异性的T细胞反应，这与治疗前的恢复纤维发育有关。这些肌营养不良蛋白特异性的T细胞有可能消除所有遗传修饰的肌肉，导致无效的疗法，并对一般的基因治疗群落提出了普遍关注的关注。当前，尚无避免转基因特异性CTL的策略，无论是先前存在的还是被诱发的治疗，并且全身长期的免疫抑制被认为是不可行的选择。然而，自然界中发现的特定病毒通过合成仅在转导细胞中抑制抗原表现的小肽来发展解决这一困境的潜在解决方案。在初步实验中，我们证明了这些病毒抑制性肽（称为VIPR）的细胞合成阻止了明确定义明确的抗原的表面表现，从而保护了转导的细胞免受宿主免疫反应的影响。在当前的建议中，我们将使用犬DMD模型（GRMD）来评估VIPR从肌营养不良蛋白特异性CTL介导的消除AAV转透明肌肉中的逃避能力。首先，我们将测试VIPR的利用是否可以阻止AAV肌肉注射后肌营养不良蛋白特异性CTL反应的诱导（AIM 1）。接下来，我们将研究VIPR的应用是否有助于AAV转导的肌肉纤维逃脱现有的肌营养不良特异性的CTL介导的消除（AIM 2）。为了降低有效的病毒装置的矢量盒大小和/或增强VIPR的逃避能力，我们将优化VIPR域并测试突变变体的免疫逃避能力（AIM 3）。通过在同一载体中输送VIPR和微型肌营养素，这种方法可确保仅在没有系统性的副作用的AAVS型细胞中减弱抗原呈递对免疫系统的影响（如使用免疫抑制药物，或通过使用调节性T细胞的应用）。总的来说，该提案概述了一种有希望的策略，即通过创建一个能够避免宿主对异物蛋白的免疫反应的AAV载体来克服我们的临床DMD观察结果和对基因治疗研究的关注。