Recombinant annexin A2 plus tPA for combination stroke therapy

重组膜联蛋白 A2 加 tPA 用于中风联合治疗

基本信息

批准号：
8103811
负责人：
XIAOYING WANG
金额：
$ 37.28万
依托单位：
MASSACHUSETTS GENERAL HOSPITAL
依托单位国家：
美国
项目类别：
财政年份：
2010
资助国家：
美国
起止时间：
2010-07-01 至 2015-06-30
项目状态：
已结题

来源：
https://reporter.nih.gov/project-details/8103811
关键词：
ANXA2 gene Adhesives Adverse effects Aftercare Angiogenic Factor Angiography Attenuated Biological Assay Biological Markers Blood - brain barrier anatomy Blood Vessels Blood Volume Blood flow Brain Brain Infarction Cerebral Ischemia Cerebrovascular Circulation Cerebrum Coagulation Process Collagen Type IV Combined Modality Therapy Complex Core-Binding Factor Critical Care Cytolysis Data Development Diffusion Dose Edema Emergency treatment Enzymes Evans blue stain Evolution Excision Extracellular Matrix Degradation Extravasation FDA approved Fibrin fragment D Fibrin split products Fibrinolytic Agents Gel Gelatinase B Generations Hematoxylin and Eosin Staining Method Hemorrhage Hypercapnia Hyperoxia In Situ Infarction Infiltration Inflammation Injury Intervention Ischemic Stroke Laminin Lead Lesion Magnetic Resonance Imaging Maps Measurement Measures Mediating Microglia Molecular Myelin Basic Proteins Neurological outcome Outcome Patients Perfusion Plasma Plasmin Plasminogen Proteins Proteolysis Rattus Recombinants Recovery Relative (related person)Reperfusion Therapy Risk Saline Stroke Testing Therapeutic Tight Junctions Time Tissues Translating Translational Research Vascular Endothelial Growth Factors Vasodilator Agents Western Blotting base behavior test brain tissue claudin-1 protein density functional outcomes hemodynamics improved indexing insight intravenous administration mortality multidisciplinary neurotoxicity novel public health relevance research study response stroke therapy thrombolysis vasoconstriction white matter

项目摘要

DESCRIPTION (provided by applicant): Intravenous administration of recombinant tPA remains the only FDA-approved and the most beneficial proven intervention for emergency treatment of stroke. However, short treatment time window, hemorrhagic transformation, poor thrombolytic perfusion rate, and neurotoxicity comprise the major limitations to the application. In this proposal, we hypothesize that recombinant Annexin A2 protein (rA2) will lower the required dose of tPA for reperfusion, while enhancing thrombolytic efficacy, and attenuating intracerebral hemorrhagic transformation. By doing so, it will prolong therapeutic time windows and improve long-term outcomes. The molecular basis for our idea is that annexin A2 accelerates the generation of clot-dissolving plasmin by assembling a fibrinolytic complex with tPA and the plasmin precursor plasminogen. Our pilot data are promising. We now propose three aims to investigate the mechanisms involved in this new combination therapy. In Aim 1, we will study thrombolytic efficacy of rA2 plus low dose tPA combination treated at 4 hrs after focal embolic stroke in rats with MR angiography to determine recanalization and reocclusion, MRI CBF to map cerebral blood flow; and MRI measurements of cerebral blood volume (CBV), microvascular volume (MVV), and vessel size index (VSI) to quantify vascular responses to thrombolytic agents and vasodilators. In Aim 2, we will investigate effects of rA2 plus low dose tPA combination therapy on neurovascular matrix proteolysis and BBB leakage treated at 4 hrs after focal embolic stroke of rats. The development of brain infarction, edema and hemorrhagic transformation will be measured and correlated with temporal profiles of MMP-9 activity, proteolytic degradation of extracellular matrix components and BBB leakage. In Aim 3, we will assess long term outcomes of rA2 plus low dose tPA combination treated at 4 hrs after stroke. Rats will be followed over 4 weeks with a battery of behavioral tests. At the end, brains are removed for H&E lesion size measurement, cerebral vessel density and tissue recovery factors VEGF, Ang-1 expression will be examined. Low-dose tPA plus rA2 will be compared with rA2 alone, low-dose and high-dose tPA alone, and vehicle saline control. If successful, these proposed experiments should provide new insight of how rA2 plus low dose tPA improve tPA stroke treatment and may ultimately yield a novel combination approach to optimize tPA-based thrombolytic stroke therapy. We believe our proposal should be directly relevant for PA-07-233, "Multidisciplinary Translational Research in Critical Care" (R01). PUBLIC HEALTH RELEVANCE: Intravenous administration of tPA is the only FDA-approved emergency treatment for ischemic stroke. Mainly because the risk of brain bleeding, only 2-5% stroke patients receive tPA in USA. Here we propose a new combination therapy of annexin A2 plus tPA, it will generate more beneficial thrombolytic enzyme plasmin with much lower tPA dose. By doing so, the combination will enhance clot lysis for blood flow restorage and reduce the risk of bleeding. These effects should prolong treatment window and improve long-term outcomes.

描述（由申请人提供）：重组TPA的静脉内给药仍然是FDA批准的唯一，是中风紧急治疗的最有益的验证干预措施。但是，短时间治疗时间窗口，出血转化，溶栓灌注率差和神经毒性构成了应用程序的主要局限性。在此提案中，我们假设重组膜联蛋白A2蛋白（RA2）将降低TPA的剂量以进行再灌注，同时提高溶栓功效，并减轻脑内出血转化。通过这样做，它将延长治疗时间窗口并改善长期结果。我们想法的分子基础是，膜联蛋白A2通过与TPA和纤溶酶前体纤溶酶纤溶酶组装纤维蛋白结合复合物来加速凝块溶解纤溶酶的产生。我们的飞行员数据很有希望。现在，我们提出了三个旨在研究这种新组合疗法所涉及的机制。在AIM 1中，我们将研究RA2的血栓溶作用，以及在具有MR血管造影的大鼠局灶性栓塞式中风后4小时治疗的低剂量TPA组合，以确定重新定性和重新牙髓，MRI CBF，以映射大脑血流；和MRI测量值（CBV），微血管体积（MVV）和血管尺寸指数（VSI），以量化对溶栓剂和血管扩张剂的血管反应。在AIM 2中，我们将研究RA2加低剂量TPA联合疗法对大鼠局灶性栓塞后4小时处理的神经血管基质蛋白水解和BBB泄漏的影响。将测量脑梗塞，水肿和出血转化的发展，并与MMP-9活性的时间谱，细胞外基质组件的蛋白水解降解和BBB泄漏相关。在AIM 3中，我们将评估RA2和中风后4小时治疗的RA2和低剂量TPA组合的长期结局。大鼠将在4周内进行一系列行为测试。最后，将检查大脑以进行H＆E病变大小测量，脑血管密度和组织回收因子VEGF，ANG-1表达。低剂量TPA Plus RA2将与单独的RA2，单独的低剂量和高剂量TPA以及媒介物盐水控制进行比较。如果成功的话，这些提出的实验应提供有关RA2加低剂量TPA如何改善TPA中风治疗的新见解，并最终可能会产生一种新型的组合方法来优化基于TPA的溶栓性中风治疗。我们认为，我们的建议应该与PA-07-233，“重症监护中的多学科翻译研究”（R01）直接相关。公共卫生相关性：静脉注射TPA是唯一针对缺血性中风的FDA批准的紧急治疗方法。主要是因为脑出血的风险，只有2-5％的中风患者在美国接受TPA。在这里，我们提出了一种新的结合疗法ANENXIN A2和TPA，它将产生更有益的溶栓酶纤溶酶，TPA剂量较低。通过这样做，该组合将增强血液流动可再生的凝块裂解并降低出血的风险。这些影响应延长治疗窗口并改善长期结局。