Targeted Gene Expression in Ischemic Brain by Intravenous Delivery

通过静脉注射在缺血性脑中靶向基因表达

• 批准号: 7876141
• 负责人: HUA SU
• 金额: $ 19.31万
• 依托单位: UNIVERSITY OF CALIFORNIA, SAN FRANCISCO
• 依托单位国家: 美国
• 财政年份: 2010
• 资助国家: 美国
• 起止时间: 2010-02-01 至 2012-01-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/7876141
• 关键词: Adverse effects; Angiogenic Factor; Angiopoietin-1; Attenuated; Blood - brain barrier anatomy; Blood Vessels; Blood flow; Brain; Capsid; Cerebrum; Cessation of life; Clinical; Critical Illness; Custom; Development; Diffuse; Distal; Dose; Extravasation; Feasibility Studies; Gene Expression; Genes; Goals; Growth; Hypoxia; In Vitro; Injection of therapeutic agent; Injury; Intravenous; Intraventricular; Ischemic Brain Injury; Ischemic Penumbra; Ischemic Stroke; LacZ Genes; Lead; Mediating; Methods; Middle Cerebral Artery Occlusion; Modeling; Mus; Myocardial Ischemia; Names; Neuronal Injury; Neurons; Normal tissue morphology; Outcome; Patients; Penetration; Pilot Projects; Procedures; Proteins; Recovery; Recovery of Function; Research Project Grants; Response Elements; Scheme; Serotyping; Small Interfering RNA; Solid; Spinal cord injury; Tail; Techniques; Technology; Testing; Therapeutic; Therapeutic Effect; Tissues; Translations; Vascular Endothelial Growth Factors; Vascular blood supply; Veins; Work; adeno-associated viral vector; angiogenesis; artery occlusion; base; brain tissue; clinical application; design; dosage; gene therapy; hypoxia inducible factor 1; improved; innovation; intravenous administration; intravenous injection; neurobehavioral; neuroprotection; neurorestoration; novel; prevent; public health relevance; research study; response; response to injury; restoration; stroke therapy; therapeutic protein; tool; transgene expression; vector

DESCRIPTION (provided by applicant): Innate compensatory responses after ischemic injury can attenuate the extent of ischemic injury and promote functional recovery. Exogenous delivery of angiogenic factors has been shown to enhance this innate response. This research project is aimed primarily at overcoming certain barriers to the translation of the "enhanced innate response to injury" paradigm to the clinical setting. For example, systemic delivery of therapeutic proteins and genes into the brain is prevented by the brain blood barrier (BBB), and intraventricular delivery results in non-specific angiogenic factor distribution and gene expression, which can cause unwanted angiogenesis in normal tissues and untoward side effects. Moreover, stereotactic injection of proteins and vectors into the ischemic penumbra requires an invasive procedure and can cause additional damage. We have generated a custom-designed adeno-associated viral vector (AAV) with two primary attributes that suit our intended purpose. First, the vector's hypoxia response elements (HRE) restricts transgene expression to ischemic tissue. Second, AAV serotype nine (AAV9) effectively pentrates the BBB, enabling intravenous adminsitration. We have named our vector H9. We propose to use intravenous (IV) delivery of H9 vectors to achieve targeted gene expression in brain ischemic foci. The payload of the novel vector will be both vascular endothelial growth (VEGF) and angiopoietin-1 (Ang-1). VEGF was chosen, because it is the most- studied angiogenic factor for ischemic stroke therapy, has angiogenic and neurogenic effects, and promotes both neuronal protection and restoration. Ang-1 was chosen, because it reduces vessel leakage caused by VEGF and works synergistically with VEGF on angiogenesis and neuroprotection. The goal of this project is to develop an innovative approach to improve the outcomes of gene-based therapies for ischemic brain injury. We plan to use a mouse permanent distal middle cerebral artery occlusion model to test our hypotheses, that (1) IV injection of H9 vector will result in targeted gene expression in the ischemic brain and (2) IV injection of H9-VEGF and H9-Ang-1 results in better outcomes than stereotactic injection. This pilot study will provide solid proof of principle for our approach, and in subsequent applications (R01), we will extend the studies to optimize vector delivery (dosage and delivery schemes); to better understand the mechanisms of the neuroprotective or neurorestorative effects of VEGF and Ang-1, and neurobehavioral recovery; and to study the feasibility of this approach for clinical application. The proposed technology is novel and, if successful, will lead to development of a more selective gene therapy for ischemic stroke. The same approach can also be applied to the treatment of spinal cord injury. PUBLIC HEALTH RELEVANCE: This project will develop a new method to induce new functional small blood vessels in the brain where the blood supply is insufficient. As result, increased blood flow will protect neurons from death.

描述（由申请人提供）：缺血性损伤后的先天性代偿反应可减轻缺血性损伤的程度并促进功能恢复。外源性递送血管生成因子已被证明可增强这种先天反应。该研究项目的主要目的是克服某些障碍的翻译“增强先天反应损伤”的范例，以临床设置。例如，治疗性蛋白质和基因向脑中的全身递送被脑血屏障（BBB）阻止，并且脑室内递送导致非特异性血管生成因子分布和基因表达，这可在正常组织中引起不希望的血管生成和不利的副作用。此外，将蛋白质和载体立体定向注射到缺血半暗带中需要侵入性操作，并且可能导致额外的损伤。我们已经产生了定制设计的腺相关病毒载体（AAV），其具有适合我们预期目的的两个主要属性。首先，载体的缺氧反应元件（HRE）限制了转基因表达缺血组织。第二，AAV血清型9（AAV 9）有效地穿透BBB，使得能够静脉内施用。我们将这个矢量命名为H9。我们建议使用静脉内（IV）交付的H9载体，以实现脑缺血灶中的靶向基因表达。新载体的有效载荷将是血管内皮生长（VEGF）和血管生成素-1（Ang-1）。选择VEGF是因为它是用于缺血性中风治疗的研究最多的血管生成因子，具有血管生成和神经生成作用，并且促进神经元保护和恢复。选择Ang-1是因为它减少VEGF引起的血管渗漏，并与VEGF协同作用于血管生成和神经保护。该项目的目标是开发一种创新的方法来改善缺血性脑损伤的基因治疗的结果。我们计划使用小鼠永久性远端大脑中动脉闭塞模型来测试我们的假设，即（1）IV注射H9载体将导致靶向基因在缺血脑中的表达和（2）IV注射H9-VEGF和H9-Ang-1比立体定向注射产生更好的结果。这项初步研究将为我们的方法提供坚实的原则证据，在随后的应用中（R 01），我们将扩展研究以优化载体递送（剂量和递送方案）;更好地了解VEGF和Ang-1的神经保护或神经恢复作用以及神经行为恢复的机制;并研究这种方法用于临床应用的可行性。这项技术是新颖的，如果成功的话，将导致缺血性中风更有选择性的基因治疗的发展。同样的方法也可以应用于脊髓损伤的治疗。 公共卫生相关性：该项目将开发一种新方法，在血液供应不足的大脑中诱导新的功能性小血管。因此，增加血流量将保护神经元免于死亡。