LENTIVIRAL VECTOR BASED GENE THERAPY FOR LIVER DISEASES

基于慢病毒载体的肝病基因治疗

• 批准号: 6846380
• 负责人: TAL KAFRI
• 金额: $ 21.83万
• 依托单位: UNIV OF NORTH CAROLINA CHAPEL HILL
• 依托单位国家: 美国
• 财政年份: 2001
• 资助国家: 美国
• 起止时间: 2001-04-01 至 2006-05-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/6846380
• 关键词: Lentivirus; biotechnology; coagulation factor IX; disease /disorder model; dogs; gene delivery system; gene therapy; hemophilia B; human immunodeficiency virus 1; laboratory mouse; liver disorder; nonhuman therapy evaluation; nucleic acid sequence; transfection /expression vector; virus genetics

DESCRIPTION (Copied from Applicant Abstract): The overall goal of this study is to validate our hypothesis that lentivirus vectors can serve as an efficient and safe platform for therapeutic gene delivery to the liver tissue. The ability of HIV-1 and other lentiviruses to transduce non-dividing cells prompt the development of an HIV-l based gene delivery system. The novel lentivirus vectors proved efficient at transducing various tissues in vivo (brain, liver, muscle, retina, and hematopoietic stem cells) without any detectable pathology. Recently, we showed that a single intraperitoneal injection of hemophilic mice with lentivirus vectors resulted in long term expression of therapeutic levels of canine factor IX. The treated mice demonstrated aPTT values equivalent to those obtained from heterozygous littermates. In addition our preliminary results indicated that cis-regulatory sequences in the lentivirus down-regulate transgene expression. These studies are most encouraging, however we believe that further improvements in: vector production, trsansgene expression, and regulation, and better characterization of the mechanism responsible for the development of inhibitory antibodies are required before we can consider the use of the lentiviral system as a safe and efficient viral vector for liver gene therapy. To facilitate safe vector production we propose to generate a novel third generation packaging cell line, which will be devoid of the Tat and all HIV-l accessory proteins. As an additional measurement of safety, we will separate the new packaging system into four stably integrated plasmids (vector, envelope, packaging, and rev). To improve transgene expression from the lentivirus vector cassette we will attempt to identify and delete inhibitory sequences from the lentivirus vector genome. To improve regulation of transgene expression we will generate an improved new inducible lentivirus vector which will exhibit minimal basal inducible promoter activity. Testing the proposed improvements in hemophilic mouse and canine animal models will allow us to characterize potential immune response against the newly synthesized factor IX. We believe that the ability to maintain therapeutic levels of factor IX in these animal models will determine the feasibility of using lentivirus vector based gene therapy to cure hemophilia B and other hepatic metabolic diseases.

描述（摘自申请人摘要）：本研究的总体目标是 验证我们的假设，即慢病毒载体可以作为一种有效的 以及将治疗基因递送至肝组织的安全平台。这 HIV-1和其他慢病毒转导非分裂细胞的能力提示 基于HIV-1的基因传递系统的开发。新型慢病毒 载体被证明可有效转导体内各种组织（脑、肝、 肌肉、视网膜和造血干细胞），没有任何可检测到的病理学。 最近，我们发现血友病小鼠单次腹腔注射 慢病毒载体导致治疗水平的长期表达 犬因子 IX。接受治疗的小鼠表现出的 aPTT 值相当于 那些从杂合同窝出生的动物获得的。另外我们初步 结果表明，慢病毒中的顺式调控序列下调 转基因表达。这些研究是最令人鼓舞的，但我们相信 进一步改进：载体生产、trsansgene 表达，以及 监管，并更好地描述负责的机制 在我们考虑之前需要开发出抑制性抗体 使用慢病毒系统作为安全高效的肝脏病毒载体 基因疗法。 为了促进安全载体生产，我们建议生成新的第三种载体 一代包装细胞系，该细胞系不含 Tat 和所有 HIV-l 辅助蛋白。作为安全性的额外衡量标准，我们将分开 新的包装系统分为四个稳定整合的质粒（载体， 信封、包装和版本）。 为了改善慢病毒载体盒的转基因表达，我们将 尝试从慢病毒载体中识别并删除抑制序列 基因组。 为了改善转基因表达的调控，我们将产生一种改进的新 具有最小基础诱导型启动子的诱导型慢病毒载体 活动。在血友病小鼠和犬科动物中测试拟议的改进 动物模型将使我们能够表征潜在的免疫反应 新合成的因子 IX。我们相信有能力维持 这些动物模型中因子 IX 的治疗水平将决定 基于慢病毒载体的基因治疗治疗B型血友病的可行性 以及其他肝脏代谢疾病。