Minimizing transgene clearance

最大限度地减少转基因清除

基本信息

批准号：
8311212
负责人：
Guangping Gao
金额：
$ 53.9万
依托单位：
HARVARD MEDICAL SCHOOL
依托单位国家：
美国
项目类别：
财政年份：
2012
资助国家：
美国
起止时间：
2012-04-01 至 2012-11-30
项目状态：
已结题

来源：
https://reporter.nih.gov/project-details/8311212
关键词：
Address Animal Model Animals Antibodies Antibody Formation Antigen Presentation Antigen-Presenting Cells Antiviral Agents Autoantigens Blood Coagulation Factor Canis familiaris Cells Defect Dendritic Cells Development Disease Dose Factor IX Frequencies Gene Transfer Genes Genome HIV HIV Infections HIV-1 Hemophilia B Hepatocyte Homologous Gene Human Immune Immune response Immunity Infection Intramuscular Intramuscular Injections LacZ Genes Literature Liver Macaca Macaca mulatta Mediating Methods MicroRNAs Modeling Mus Muscle Oryctolagus cuniculus Primates Process Proteins Recombinants Regulation Research SIV Serum Sorting - Cell Movement Specificity Technology Therapeutic Therapeutic Uses Tissues Transgenes Viral Viral Physiology Virus Inhibitors adeno-associated viral vector base cell type design enhanced green fluorescent protein gene replacement therapy gene therapy immune clearance improved inhibitor/antagonist novel strategies null mutation prevent programs promoter response therapeutic gene vector vector genome

Address Animal Model Animals Antibodies Antibody Formation Antigen Presentation Antigen-Presenting Cells Antiviral Agents Autoantigens Blood Coagulation Factor Canis familiaris Cells Defect Dendritic Cells Development Disease Dose Factor IX Frequencies Gene Transfer Genes Genome HIV HIV Infections HIV-1 Hemophilia B Hepatocyte Homologous Gene Human Immune Immune response Immunity Infection Intramuscular Intramuscular Injections LacZ Genes Literature Liver Macaca Macaca mulatta Mediating Methods MicroRNAs Modeling Mus Muscle Oryctolagus cuniculus Primates Process Proteins Recombinants Regulation Research SIV Serum Sorting - Cell Movement Specificity Technology Therapeutic Therapeutic Uses Tissues Transgenes Viral Viral Physiology Virus Inhibitors adeno-associated viral vector base cell type design enhanced green fluorescent protein gene replacement therapy gene therapy immune clearance improved inhibitor/antagonist novel strategies null mutation prevent programs promoter response therapeutic gene vector vector genome

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项目摘要

A recent study proved the concept that rAAV-mediated intramuscular delivery of scFv immunoadhesins to rhesus macaques can generate sustained high serum levels of these inhibitors, and protect study animals from a high-dose SIV challenge. However, some of the treated animals in that study developed anti-immunoadhesin antibody responses, resulting in clearance of antiviral inhibitors. Immune clearance of this sort has been well documented in the rAAV gene-therapy literature: expression of foreign proteins from rAAVs in large animal models can in general elicit strong trangene-directed immunity, leading to host clearance of the expressed transgene. Indeed immune clearence remains a key challenge to further translational development of rAAV-delivered therapies. It is therefore necessary to better define immune processes contributing to anti-inhibitor antibody responses, and to develop novel strategies to prevent clearance of expressed transgenes. These are the main objectives of Project 2. We proposed the following studies to accomplish these objectives: 1). To limit transduction and antigen presentation of rAAV-immunoadhesin in unintended target cells and tissues by evaluating a panel of muscle specific promoters for promoter strength, tissue specificity and feasibility for use in the packaging size-limited rAAV genome. 2). To detarget rAAV transduction from antigen presenting cells by harnessing endogenous miRNAs for dendritic cell specific post-transcriptional transgene silencing. 3). To induce sustained systemic tolerance to immunoadhesin expression by hepatotropic rAAV8-mediated and liver-specific transduction. These studies will generate an AAV vector genome optimized to limit clearence of expressed transgenes, an objective critical to the therapeutic use of AAV vectors in many contexts.

最近的一项研究证明了RAAV介导的SCFV免疫粘附素的肌内递送至恒河猕猴可以产生这些抑制剂的高血清水平，并保护研究动物来自高剂量SIV挑战。然而，该研究中的一些经过治疗的动物发展出抗免疫粘附素抗体反应，导致抗病毒抑制剂的清除。免疫清除在RAAV基因疗法文献中已经有充分的文献记载：外蛋白的表达大型动物模型中的RAAV总体上可以引起强大的trangene指导的免疫力，从而导致宿主清除表达的转基因。确实，免疫清除仍然是进一步的关键挑战 RAAV分配疗法的翻译发展。因此，有必要更好地定义免疫力有助于抗抑制剂抗体反应的过程，并制定新的策略以防止清除表达的转基因。这些是项目2的主要目标。我们提出了以下研究来实现这些目标： 1）。限制在意外靶细胞和通过评估肌肉特异性启动子的启动子强度，组织特异性和在包装尺寸有限的RAAV基因组中使用的可行性。 2）。通过利用内源miRNA的抗原呈递细胞转导RAAV的RAAV转导树突状细胞特异性转录后转基因沉默。 3）。诱导肝RAAV8介导的对免疫粘附素表达的持续全身性耐受性和肝特异性转导。这些研究将产生优化的AAV载体基因组，以限制表达转基因的清晰度，即客观对于在许多情况下对AAV向量的治疗使用至关重要。