Activated Neutrophilic Exosome as Biomarker and Therapeutic Target in COPD

项目摘要/摘要： 慢性阻塞性肺疾病(COPD)是全世界第四大致死原因 是一种慢性炎症性疾病，被认为至少部分是由 蛋白水解酶-抗蛋白酶平衡紊乱。最近的发现表明 中性粒细胞弹性蛋白酶(NE)等蛋白酶可与外切体相关 由中性粒细胞(PMN)释放。外周小体是由细胞释放到 环境。NE与外切体结合时具有酶活性，但它是 明显抵抗这种形式的α-1抗胰蛋白酶(α-1AT)的抑制。外体NE是 在小鼠模型中引起COPD的能力比可溶性NE高几倍，并且 外切体本身能够穿过组织平面并结合到结构上 肺中的蛋白质，如I型胶原，将蛋白质分解集中在其底物上。 重要的是，来自中性粒细胞的外体能够引起NE依赖 在小鼠肺泡灌洗液(BALF)中发现了小鼠的肺泡破坏 研究对象为慢性阻塞性肺疾病患者，但不是健康对照。由于这些发现，似乎有可能 这种外切体相关形式的去甲肾上腺素对细胞外基质可能更重要 破坏(从而COPD的发病机制)比常规测量的可溶性NE。 这项研究项目将在三年内量化PMN衍生的NE+外切体负荷 COPD患者和无梗阻神经受试者的良好表型队列 吸烟者和现任/前任吸烟者对照受试者。此外，PMN派生的， 将评估痰和血清的Ne+外切体图谱以确定生物标记物 与BALF相比，使用侵入性更小的衍生标本，这一过程的实用性。这些 这些发现将与COPD疾病的各种临床验证方法相关联。 进展、症状负担以及疾病亚型，并将相互关联 随着COPD在这种疾病的高危人群中的发展。此外，这一点 该项目将开发和优化致病外切体转移的动物模型， 阐明去甲肾上腺素与中性粒细胞外切体表面结合的机制及其研究进展 设计合理的策略来中断外切体的致病性。这些研究将形成 PMN来源的NE+外切体AS的使用和进一步研究的基础 疾病活动性的生物标志物和潜在的治疗靶点。

Project Summary/Abstract: Chronic obstructive pulmonary disease (COPD), the fourth leading cause of death in the world, is a chronic inflammatory disease thought to be driven at least in part by derangements of protease-antiprotease balance. Recent discoveries have suggested that proteases such as neutrophil elastase (NE) can be associated with exosomes released by neutrophils (PMNs). Exosomes are nanovesicles released by the cell into the environment. NE is enzymatically active when associated with exosomes yet it is markedly resistant to inhibition by α-1 antitrypsin (α-1AT) in this form. Exosomal NE is several log-fold more potent in causing COPD in mouse models than soluble NE, and the exosomes themselves are able to traverse tissue planes and bind to structural proteins in the lung such as type I collagen, focusing the proteolysis upon its substrate. Importantly, exosomes derived from PMNs that are capable of causing NE-dependent alveolar destruction in mice have been found in bronchoalveolar lavage fluid (BALF) of subjects with COPD, but not healthy controls. Because of these findings, it seems likely that this exosome-associated form of NE may be more important to extracellular matrix destruction (and thus COPD pathogenesis) than conventionally measured soluble NE. This research project will quantify the PMN-derived, NE+ exosome burden within three well-phenotyped cohorts of subjects with COPD as well as non-obstructed never smoker and current/former smoker control subjects. Furthermore, the PMN-derived, NE+ exosome profile of sputum and serum will be assessed to define the biomarker utility of this process using less invasively derived specimens than BALF. These findings will be correlated with various clinically validated measures of COPD disease progression, symptom burden as well as disease sub-phenotype and will be correlated with development of COPD among subjects at risk for this disease. Moreover, this project will develop and optimize an animal model of pathogenic exosome transfer, delineate the mechanism of NE binding to the PMN exosome surface, and advance rational strategies designed to interrupt exosome pathogenicity. These studies will form the foundation for the use and further study of PMN-derived, NE+ exosomes as biomarkers of disease activity and potential therapeutic targets.