Mechanisms of platelet exosome-mediated acute chest syndrome in sickle cell disease

血小板外泌体介导的镰状细胞病急性胸部综合征的机制

• 批准号: 9918971
• 负责人: Matthew D Neal
• 金额: $ 77.39万
• 依托单位: UNIVERSITY OF PITTSBURGH AT PITTSBURGH
• 依托单位国家: 美国
• 财政年份: 2019
• 资助国家: 美国
• 起止时间: 2019-04-22 至 2023-03-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/9918971
• 关键词: Acute; Acute Lung Injury; Affect; American; Attenuated; Binding; Biochemical; Biocompatible Materials; Blood; Blood Platelets; Blood flow; CASP1 gene; Drug Delivery Systems; Drug Targeting; Dyes; Encapsulated; Functional disorder; Hemorrhage; Image; In Vitro; Inflammasome; Injury; Interleukin-1 Receptors; Interleukin-1 beta; Lipopolysaccharides; Lung; Mediating; Microcirculation; Microfluidics; Microscopy; Modeling; Mus; Pathogenesis; Patients; Physiological; Platelet Count measurement; Platelet aggregation; Role; Secondary to; Sickle Cell Anemia; Signal Transduction; Site; TLR4 gene; Testing; Thrombocytopenia; Thrombosis; Time; Transgenic Organisms; acute chest syndrome; arteriole; exosome; extracellular vesicles; high risk; human disease; in vivo; innovation; interleukin-1beta-converting enzyme inhibitor; live cell imaging; lung imaging; lung injury; mortality; multi-photon; nanomedicine; nanoparticle; neutrophil; novel; novel therapeutics; peripheral blood; prevent; recruit; vaso-occlusive crisis

PROJECT SUMMARY Acute chest syndrome (ACS), a type of acute lung injury, is one of the leading causes of mortality in Sickle Cell Disease (SCD). Current treatments for ACS are primarily supportive, and there is a critical need for rescue therapies that can halt the progression of ACS. ACS is often a sequela of acute systemic vaso-occlusive crisis and preceded by thrombocytopenia. However, the role of platelets in the pathogenesis of ACS remains largely unknown. We hypothesize that ACS involves NLRP3-inflammasome mediated release of IL-1β-carrying platelet exosomes in SCD, which promote platelet-neutrophil aggregation leading to arrest of blood flow in lung. We also propose that targeted inhibition of TLR4/NLRP3-caspase-1 signaling in platelets is a potential therapy for ACS. To test this hypothesis, we will use an integrative physiologic approach that utilizes our recently validated model of lipopolysaccharide (LPS) induced vaso-occlusive crisis in transgenic SCD mice, in vivo multi-photon excitation (MPE) imaging of the lung vasculature in live SCD mice, live cell imaging of SCD human blood flowing in microfluidic channels in vitro, SCD mice lacking caspase-1 in platelets and nanoparticle tracking analyses of exosomes. In Aim 1, we will determine whether release of IL-1β-carrying platelet exosomes in SCD promote platelet-neutrophil aggregates in pulmonary arterioles that result in loss of blood flow in the lung. In Aim 2, we will determine whether TLR4/NLRP3-inflammasome mediated activation of caspase-1 in platelets is responsible for release of IL-1β-carrying exosomes from platelets in SCD. We have developed platelet-targeted nanomedicine (PTN) that specifically recruits to sites of platelet aggregation and thrombosis in vivo for targeted drug delivery. In Aim 3, we will determine whether PTNs carrying TLR4 or caspase-1 inhibitors, or IL-1 receptor antagonist (IL-1RA) can selectively recruit to sites of platelet aggregation to block platelet exosome release and signaling, and stop platelet-neutrophil aggregation in the lung vasculature of SCD mice. This study will identify a novel, platelet-derived exosome-mediated mechanism contributing to ACS. The findings will also establish that delivery of TLR4 or caspase-1 inhibitor, or IL-1RA encapsulated in PTNs can be a potential rescue therapy for ACS in high risk SCD patients presenting with vaso-occlusive crisis and thrombocytopenia.

项目摘要 急性胸部综合征（ACS）是一种急性肺损伤，是镰状细胞死亡率的主要原因之一 疾病（SCD）。当前对AC的治疗主要得到支持，并且急需救援需要 可以停止ACS进展的疗法。 ACS通常是急性全身性血管成熟危机的续集 并在血小板减少症之前。但是，血小板在ACS发病机理中的作用在很大程度上仍然存在 未知。我们假设ACS涉及NLRP3-炎症小子介导的携带IL-1β的血小板的释放 SCD中的外泌体，促进血小板中性嗜嗜性粒聚集，导致肺中血流阻止。我们也是 针对血小板中TLR4/NLRP3-Caspase-1信号转导TLR4/NLRP3-Caspase-1信号的建议是ACS的一种潜在疗法。 为了检验这一假设，我们将使用一种使用我们最近验证的模型的综合生理方法 脂多糖（LPS）诱导的转基因SCD小鼠的血管成熟危机，体内多光子兴奋 （MPE）活体SCD小鼠中肺脉管系统的成像，SCD人体血液的活细胞成像 体外微流体通道，在血小板中缺乏caspase-1的SCD小鼠和纳米颗粒跟踪分析的分析 外泌体。在AIM 1中，我们将确定在SCD中释放携带IL-1β的血小板外泌体是否促进 肺动脉菌中血小板中性嗜性骨聚集体导致肺部血流损失。在AIM 2中，我们 将确定tlr4/nlrp3-膜体介导的血小板中caspase-1的激活是负责 用于从SCD中的血小板中释放IL-1β的外泌体。我们已经开发了血小板靶向的 纳米医学（PTN）专门向靶向靶向的体内血小板聚集和血栓形成部位报告 药物输送。在AIM 3中，我们将确定携带TLR4或caspase-1抑制剂的PTN或IL-1受体是 拮抗剂（IL-1RA）可以选择性地募集到血小板聚集的部位，以阻止血小板外泌体释放和 信号传导，并在SCD小鼠的肺脉管系统中停止血小板中性嗜性聚集。这项研究将确定 新型的，血小板来源的外泌体介导的机制，促成ACS。调查结果还将确定 TLR4或caspase-1抑制剂的递送，或封装在PTN中的IL-1RA可能是潜在的救援疗法 高风险SCD患者的ACS出现了血管熟悉的危机和血小板减少症。