PROTEIN DELIVERY INTO THE CENTRAL NERVOUS SYSTEM

治疗性肽和蛋白质穿过血脑的递送 已经证明，进入中枢神经系统的血脑屏障（BBB）是一种主要的 治疗神经系统疾病的障碍。选择性神经元丢失 在ALS、阿尔茨海默氏症、帕金森氏症、脑缺血和其他 神经退行性疾病，加上越来越多的证据表明， 神经营养因子对各种退行性变有保护作用， 病变，支持了各种各样的治疗作用， 神经营养因子及其衍生物在治疗这些疾病中的应用 (e.g., NGF、BDNF、NT-3、4/5、CNTF、GDNF、IGF-1、PNT-1等）。同样，SOD， BDNF和FGF已经被认为在防止海马神经元损伤中具有作用。 脑缺血后神经元损伤。感染的风险， 导管凝血、神经外科手术成本、扩散限制超出 心室表面到脑实质，在那里这些因素是 需要影响退化神经元的离散群体， CSF的清除强调了开发新的 用于治疗神经系统的非侵入性药物递送形式 人类的神经系统疾病我们已经开发了方法， 定量BBB对肽和蛋白质的渗透性， 适当校正由药物占据的残余血浆体积， 用第二种放射性示踪剂 相同的蛋白质。这项技术使我们能够发展 促进靶向神经系统递送治疗药物的策略 蛋白质注射后。 这些战略包括 鉴定具有高渗透性的蛋白质， 用于递送治疗化合物的载体。第二个策略是 治疗性蛋白质的化学或生物化学修饰， 增加渗透性同时仍保持其生物活性。 关键 治疗神经系统疾病不仅是增强 治疗剂胃肠外给药后BBB的渗透性 蛋白质，而且：1）必须保持蛋白质的生物活性 在修饰或偶联到载体上后，2）蛋白质必须 递送至受影响的神经元或神经胶质细胞的离散群体， 神经系统，3）蛋白质在递送后必须保持其生物活性， 4）最重要的是，它必须能够引起生物反应， 这群细胞在这份拨款申请中，我们计划测试 我们的策略增加NGF的渗透性的有效性， BBB与胃肠外给药后的天然蛋白质相比。的 然后，将评估产生最高渗透率的策略， 三种动物模型来测试所递送的修饰的 神经生长因子在离散脑胆碱能神经元中引发生物反应 与天然NGF相比，胃肠外给药后的区域。这些 这些结果将对治疗人类神经系统疾病产生直接影响。 疾病

Delivery of therapeutic peptides and proteins across the blood-brain barrier (BBB) into the central nervous system has proven to be a major obstacle in treating neurological diseases. The selective neuronal loss observed in ALS, Alzheimer's, Parkinson's, cerebral ischemia, and other neurodegenerative diseases, coupled with the growing body of evidence that neurotrophic factors have a protective effect against various degenerative lesions, has supported a therapeutic role for a large variety of neurotrophic factors and their derivatives in treating these diseases (e.g., NGF, BDNF, NT-3,4/5,CNTF, GDNF, IGF-1 PNT-1, etc.). Similarly, SOD, BDNF, and FGF have been suggested to have a role in preventing hippocampal neuronal damage following cerebral ischemia. The risk of infection, catheter clotting, neurosurgical costs, diffusional limitations beyond the ventricular surface to the parenchyma of the brain where these factors are needed to affect discrete populations of degenerating neurons, and rapid clearance by the CSF emphasize the considerable need to develop novel forms of non-invasive drug delivery to the nervous system for treatment of neurological diseases in humans. We have developed methodologies to quantify the permeability of the BBB to peptides and proteins with appropriate correction for the residual plasma volume occupied by the protein in the capillary bed of brain with a second radioactive tracer of the same protein. This technology has allowed our development of strategies to facilitate targeted nervous system delivery of therapeutic proteins after parenteral a ministration. These strategies include the identification of proteins with high permeabilities which could be used as carriers for the delivery of therapeutic compounds. A second strategy is the chemical or biochemical modification of therapeutic proteins to increase permeability while still preserving their bioactivity. Crucial to the treatment of neurological disease is not only the enhanced permeability at the BBB after parenteral administration of the therapeutic protein but also: 1) the bioactivity of the protein must be preserved after modification or coupling to a carrier, 2) the protein must be delivered to a discrete population of affected neurons or glia within the nervous system, 3) the protein must retain its bioactivity after delivery, and 4) most importantly, it must be capable of soliciting a bioresponse in this population of cells. In this grant proposal, we plan to test the efficacy of our strategies for increasing the permeability of NGF at the BBB compared to the native protein after parenteral administration. The strategy that produces the highest permeability will then be evaluated in three animal models to test the effectiveness of the delivered modified NGF in soliciting a bioresponse in cholinergic neurons in discrete brain regions after parenteral administration compared to the native NGF. These results will have direct implications for treating human neurological disease.