Leveraging platelet signal transduction for personalized antiplatelet therapy

利用血小板信号转导进行个性化抗血小板治疗

• 批准号: 10480329
• 负责人: David Barrios
• 金额: $ 25.96万
• 依托单位: PLATELETDIAGNOSTICS, LLC
• 依托单位国家: 美国
• 财政年份: 2022
• 资助国家: 美国
• 起止时间: 2022-05-06 至 2024-01-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/10480329
• 关键词: Affect; Agitation; Agonist; Antibodies; Antiplatelet Drugs; Aspirin; Awareness; Biological Assay; Blood; Blood Platelet Antagonists; Blood Platelet Disorders; Blood Platelets; Cardiovascular Diseases; Cardiovascular system; Caring; Cessation of life; Characteristics; Clinical Data; Clinical Research; Clinical Trials; Clinics and Hospitals; Complex; Consensus; Consumption; Coronary Arteriosclerosis; Data; Detection; Development; Devices; Diagnostic; Diagnostic Reagent Kits; Disease; Dose; Drug Monitoring; Effectiveness; Electrolytes; Ensure; Enzyme-Linked Immunosorbent Assay; Enzymes; Equipment; Fluorescence; Future; Goals; Gold; Health Personnel; Hemorrhage; Hospitals; Human; Immunoassay; Immunoglobulin G; Intracranial Hemorrhages; Ketorolac; Knowledge; Laboratories; Lead; Life; Measures; Mechanics; Mediating; Monitor; Myocardial Infarction; Obesity; Oryctolagus cuniculus; Outcome; Pathologist; Pathway interactions; Patients; Performance; Persons; Pharmaceutical Preparations; Phosphorylation; Phosphorylation Site; Physicians; Platelet Activation; Platelet Function Tests; Platelet aggregation; Positioning Attribute; Preparation; Process; Proteins; Protocols documentation; Quality Control; Reagent; Recurrence; Reproducibility; Resistance; Risk; Role; Running; Savings; Sensitivity and Specificity; Signal Pathway; Signal Transduction; Site; Specificity; Standardization; Stroke; System; Testing; Thrombosis; Time; Training; United States; assay development; base; clopidogrel; commercialization; cost; detection limit; fluorophore; improved; improved outcome; instrumentation; laboratory equipment; mortality; non-compliance; novel strategies; patient responsibilities; phase 2 study; platelet function; point of care; point of care testing; response

Project Summary/Abstract Platelet-mediated thrombosis causes both coronary arterial disease (CAD) and stroke, the first and fifth most common causes of mortality in the US. Antiplatelet agents, typically aspirin and/or clopidogrel, significantly improve survival in patients with CAD or stroke and have remained a mainstay of treatment for more than two decades. Yet despite the consensus that platelet inhibition with aspirin and/or clopidogrel improves outcomes, recurrence remains common and there is a growing awareness that inappropriate dosing of antiplatelets contributes to poor outcomes. On one hand, under-dosing of antiplatelet agents can result in increased likelihood of CAD and stroke recurrence. On the other hand, over-dosing can lead to increased bleeding risk including fatal intracranial hemorrhage. The scope of this problem is enormous. More than 50 million US citizens have been prescribed aspirin and/or clopidogrel for cardiovascular disease. Inappropriate responsiveness to either drug occurs in approximately 25% of patients. Yet despite the unmet need for improved monitoring strategies, the gold standard for platelet function testing remains platelet aggregometry, which is fundamentally unchanged since its development 50 years ago. Newer point-of-care (POC) devices have been marketed but require expensive equipment and consumables and/or have complex readouts and do not lend themselves to the workflow of high-volume hospitals and doctors’ offices. Thus, there is a vital need for a platelet function assay that can be simply ordered by physicians and batched to be performed inexpensively in a central laboratory, similarly to how a CBC or electrolytes are tested. In evaluating the response of platelet signaling pathways to antiplatelet agents, we have found that the platelet protein Drp1 is under the control of a dual phosphorylation system. One phosphorylation site (Drp1-Ser616) is phosphorylated in response to platelet agonists and inhibited by antiplatelet agents. A second site (Drp1-Ser637) is phosphorylated in response to platelet antagonists. This dual phosphorylation system is extremely sensitive to inhibition by antiplatelet agents and is well-suited for formatting to monitor antiplatelet therapy. Our assay has shown strong correlation with aggregometry in two ongoing clinical studies; however, these studies have also underscored the opportunity for important improvements. We will pursue 3 aims to evaluate the hypothesis that the phosphorylation of Drp1 can be leveraged to develop a new strategy for rapid, inexpensive monitoring of antiplatelet therapy. In Aim 1, our current assay will be evaluated for conversion to a fluorescence-based assay to measure both the level of S616 pDrp1 as well as the total level of Drp1 in the same well. In Aim 2, we will establish simple pre-analytical steps for use in a central laboratory and optimize agonist conditions to precisely define our testing panel. Assay characteristics such as sensitivity, specificity, precision, and accuracy of the pDrp1 assay will be determined in Aim 3 to ensure quality control and standardization between laboratories and enable large-scale phase II studies.

项目摘要/摘要 血小板介导的血栓形成引起冠状动脉疾病（CAD）和中风，第一和第五大多 美国死亡率的常见原因。抗血小板剂，通常是阿司匹林和/或氯吡格雷，显着 改善CAD或中风患者的生存率，并保持了两个以上的治疗中流 几十年。尽管达成共识，即对阿司匹林和/或氯吡格雷的血小板抑制可改善预后，但 复发仍然很普遍，并且越来越意识到不适当的抗piplatelets剂量 有助于不良的结果。一方面，抗血小板剂的剂量不足可能导致可能性增加 CAD和中风复发。另一方面，过度剂量会导致出血风险增加，包括致命 颅内出血。这个问题的范围是巨大的。超过5000万美国公民已经 为心血管疾病开张的阿司匹林和/或氯吡格雷。对任何一种药物的不适当响应能力 大约25％的患者发生。然而，希望对改进监视策略的未满足需求， 血小板功能测试的黄金标准仍然是血小板聚集的，这从根本上没有变化 自50年前的发展以来。较新的护理点（POC）设备已销售，但需要 昂贵的设备和消耗品和/或具有复杂的读数，并且不适合 大量医院和医生办公室的工作流程。这是对血小板功能测定的重要需求 可以简单地由医生订购，并在中央实验室中廉价地进行， 类似于CBC或电解质的测试方式。在评估血小板信号通路对 抗血小板药物，我们发现血小板蛋白DRP1在双重磷酸化的控制之下 系统。一个磷酸化位点（DRP1-SER616）响应血小板激动剂而被磷酸化并抑制 由抗血小板剂。第二个位点（DRP1-SER637）响应血小板拮抗剂而被磷酸化。这 双磷酸化系统对抗血小板剂的抑制极为敏感，非常适合 格式化以监测抗血小板疗法。我们的测定表现出与两者中的聚集的密切相关性 正在进行的临床研究；但是，这些研究也强调了重要的机会 改进。我们将追求3个目标，以评估DRP1的磷酸化的假设 利用以制定一种新的策略来快速，廉价地监测抗血小板疗法。在AIM 1中，我们的当前 测定将评估转换为基于荧光的测定，以测量S616 PDRP1的水平 以及同一井中的DRP1的总级别。在AIM 2中，我们将建立简单的分析前步骤 在中央实验室并优化激动剂条件以精确定义我们的测试面板。测定特征 诸如PDRP1测定的灵敏度，特异性，精度和准确性将在AIM 3中确定，以确保 实验室之间的质量控制和标准化并实现了大规模II期研究。