Thrombolysis Profiles in tPA Response

 描述（由申请人提供）：静脉注射组织纤溶酶原激活剂（tPA）是急性缺血性卒中的有效治疗方法，但在FDA批准近20年后，其利用率仍然很低，高达80%的接受tPA治疗的患者没有显示出有益的反应。目前，tPA在人体血液中的作用机制和大多数患者无反应的原因都还不清楚。为了开发真实的实时监测血液中tPA活性的临床方法，以指导个体患者的治疗，我们的目的是 为了更好地了解tPA的临床作用，特别是关于其在血液中的多效性信号传导。我们假设tPA疗效在循环中具有可测量和可量化的特征，凝血和溶栓途径中微妙平衡的扰动与疗效差有关。比较tPA应答者与无应答者，我们采用了一种组合方法，包括传统的以及创新的质谱（MS）技术。作为切入点，我们专注于我们的初步数据表明是关键的两个方面：ADAMTS 13/vWF途径，它在凝块形成和溶解中发挥作用，并受到tPA的影响，以及糖化白蛋白，它可能螯合tPA，导致糖尿病患者的预后较差。目标1：在应答者与非应答者中，通过探索ADAMTS 13/vWF轴/途径、测量ADAMTS 13和vWF水平以及通过ADAMTS 13特异性vWF底物片段评估ADAMTS 13活性来表征tPA应答。我们假设tPA应答者ADAMTS 13水平和活性升高，vWF降低。目标二：通过探讨糖化白蛋白（高水平糖化白蛋白是糖尿病的特征）的作用，研究糖尿病卒中患者的无应答。我们假设糖化白蛋白在无应答者中更高，糖化白蛋白螯合tPA，从而降低tPA在糖尿病患者中的疗效。我们将使用创新的蛋白质组学技术来检查个体患者血液中“粘”在白蛋白上的分子，我们假设糖化白蛋白比非糖化白蛋白螯合更多的tPA。有三个合作的美国中心（MGH，BWH，UMass医学院）和第四个单独的确认队列（Vall d 'Hebron医院，巴塞罗那）-我们能够以足够的速度招募患者，以便根据初步数据进行最保守的功效计算。我们令人鼓舞的试验数据、IRB批准的已发布SOP和详细的纵向结局指标分析计划（调整多种合并症）证明了招募和分析的可行性， 直接支持我们的假设和方法。

 DESCRIPTION (provided by applicant): Intravenous tissue plasminogen activator (tPA) is an effective treatment for acute ischemic stroke, but nearly two decades after FDA approval, its utilization remains low, and up to 80% of patients who receive tPA show no beneficial response. Currently, neither the mechanisms underlying tPA's effects in human blood nor the reasons for most patients' failure to respond are well understood. In order to develop clinical methods of monitoring tPA's activity in blood in real time, to guide treatment for individual patients, we aim to better understand tPA's clinical effects, especially with respect to its pleiotropic signaling within the blood. We hypothesize that tPA efficacy has a measurable and quantifiable signature in the circulation, and that perturbation of a delicate balance in coagulation and thrombolysis pathways is related to poor efficacy. Comparing tPA responders vs. non-responders, we employ a combined approach including conventional as well as innovative mass spectrometry (MS) techniques. As points of entry, we focus on two aspects that our preliminary data suggest are pivotal: the ADAMTS13/vWF pathway which plays a role in clot formation and lysis and is affected by tPA, and glycated albumin, which may sequester tPA leading to poorer outcomes for diabetic patients. Aim 1: Characterize tPA response by exploring the ADAMTS13/vWF axis/pathway, measuring levels of ADAMTS13 and vWF, and assessing ADAMTS13 activity by means of ADAMTS13-specific vWF substrate fragments, in responders vs. non-responders. We hypothesize that tPA responders will have elevated ADAMTS13 levels and activity, and decreased vWF. Aim 2: Investigate non-response in diabetic stroke patients by exploring the role of glycated albumin, high levels of which are characteristic of diabetes. We hypothesize that glycated albumin is higher in nonresponders, and that glycated albumin sequesters tPA, thereby diminishing tPA's efficacy in diabetic patients. We will use innovative proteomic techniques to examine the molecules "stuck" to albumin in individual patients' blood, and we hypothesize that glycated albumin sequesters more tPA than non-glycated albumin. With three collaborating US centers (MGH, BWH, UMass Medical School), and a fourth separate confirmation cohort (Vall d'Hebron Hospital, Barcelona) - we are able to enroll patients at a pace sufficient for our most conservative power calculation based on preliminary data. Our encouraging pilot data, IRB-approved published SOP and detailed analysis plan for longitudinal measures of outcome, adjusting for multiple co-morbidities, demonstrate the feasibility of recruitment and analysis, and directly support our hypotheses and approach.