Neuroprotection in Stroke w/ Recombinant Fusion Protein

描述(申请人提供)：中风是第三大致死原因，每年影响美国近100万人。在美国，中风幸存者的康复费用每年超过400亿美元。中风的衰弱效应源于缺血性损伤后脑细胞的损失。脑细胞不会立即死亡，而是会在几个小时内失效。这种脑细胞的死亡可以通过神经营养因子来防止，这一过程被称为神经保护。如果在中风后3小时内将神经营养素直接注射到大脑中，那么超过一半的受影响脑细胞可以被挽救。目前还没有适用于中风患者的神经保护剂，因为神经营养素和其他潜在的神经保护剂不会穿过血脑屏障(BBB)。血脑屏障问题不太可能很快得到解决，因为美国没有一家制药公司有针对血脑屏障药物的靶向计划。该公司的专长是开发血脑屏障药物靶向技术，并通过基因工程设计了一种分子特洛伊木马，它通过特定的受体运输系统穿过人类的血脑屏障。在本工作中，神经营养因子将通过基因工程将神经营养因子融合到分子特洛伊木马中，以生产一种新型的重组融合蛋白。这种融合蛋白将是一个双功能分子，它将结合(A)BBB受体/转运体，使其能够在静脉给药后通过受体介导的转运进入大脑，以及(B)脑细胞上神经营养因子的同源受体，以诱导神经保护。第一阶段SBIR赠款的目标是(I)生产一种产生融合蛋白的新型表达载体，(Ii)在细胞中表达融合蛋白，以及(Iii)通过受体特异性分析证明融合蛋白的双功能保留。这项工作将为第二阶段的研究提供基础，这将使大规模生产IND急性治疗人类中风所需的药理学/毒理学研究所需的融合蛋白成为可能。

DESCRIPTION (PROVIDED BY APPLICANT): Stroke is the third leading cause of death and affects nearly 1 million people in the U.S. each year. The cost for rehabilitation of stroke survivors is over $40 billion per year in the U.S. The debilitating effects of stroke derive from the loss of brain cells following the ischemic insult. Brain cells do not die instantly, but rather expire over several hours. This death of brain cells can be prevented by neurotrophic factors, a process called neuroprotection. If neurotrophins are injected directly into the brain within 3 hours of the stroke, then over half of affected brain cells can be saved. There presently is no neuroprotective agent available for stroke patients, because the neurotrophins, and other potential neuroprotective agents, do not cross the blood-brain barrier (BBB). It is unlikely that the BBB problem will be soon solved, because no pharmaceutical company in the U.S. has a BBB drug-targeting program. The Company's expertise is in the development of BBB drug targeting technologies, and has genetically engineered a molecular Trojan horse that crosses the human BBB via a specific receptor-transport system. In the present work, a neurotrophic factor will be fused to the molecular Trojan horse with genetic engineering for production of a novel recombinant fusion protein. This fusion protein will be a bi-functional molecule, and will bind both (a) the BBB receptor/transport, to enable receptor-mediated transport into brain following intravenous administration, and (b) the cognate receptor of the neurotrophic factor on brain cells, to induce neuroprotection. The goals of this phase I SBIR grant are to (i) produce a novel expression plasmid that produces the fusion protein, (ii) express the fusion protein in cells, and (iii) demonstrate retention of bifunctionality of the fusion protein with receptor-specific assays. This work will provide the basis for studies in phase 2, which will enable large-scale production of the fusion protein for Pharmacology/Toxicology studies required for an IND for the acute treatment of human stroke.