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补偿反应可以减轻缺血性损伤的程度并促进功能恢复。血管生成因子的外源递送已被证明可以增强这种先天反应。该研究项目的主要目的是克服某些障碍，即“增强了对伤害的先天反应”对临床环境的范式。例如，脑血液屏障（BBB）预防了治疗蛋白和基因进入大脑的全身性递送，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，这可能会导致正常组织中的不良血管生成和不耐心的副作用。此外，立体定向注射蛋白质和向量进入缺血性半阴茎需要侵入性手术，并可能造成额外的损害。我们已经产生了一个定制设计的腺相关病毒载体（AAV），其两个主要属性适合我们的预期目的。首先，载体的缺氧反应元件（HRE）将转基因表达限制为缺血组织。其次，AAV血清型九（AAV9）有效地对BBB进行了pentration，从而实现了静脉内攻击。我们命名了我们的矢量H9。我们建议使用H9载体的静脉内（IV）递送来实现脑缺血灶中的靶向基因表达。新型矢量的有效载荷将是血管内皮生长（VEGF）和Angiopoietin-1（ANG-1）。之所以选择VEGF，是因为它是缺血性中风治疗的最多研究的血管生成因子，具有血管生成和神经源性作用，并促进了神经元保护和恢复。选择了Ang-1，因为它减少了由VEGF引起的血管泄漏，并与VEGF协同作用在血管生成和神经保护方面。该项目的目的是开发一种创新的方法来改善基于基因的缺血性脑损伤疗法的结果。我们计划使用小鼠永久远端脑动脉闭塞模型来测试我们的假设，（1）IV注射H9载体将导致缺血性脑中靶向基因表达，并且（2）IV注射H9-VEGF和H9-ANG-1在比刻板式注射更好的效果中结果。这项试验研究将为我们的方法提供可靠的原理证明，在随后的应用中（R01），我们将扩展研究以优化矢量输送（剂量和输送方案）；更好地理解VEGF和ANG-1的神经保护或神经遗传作用的机制，以及神经行为恢复；并研究这种方法对临床应用的可行性。提出的技术是新颖的，如果成功，将导致为缺血性中风的更具选择性的基因疗法发展。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来诱导血液供应不足的大脑中新功能的小血管。结果，血液流量增加将保护神经元免受死亡。