Platelet adhesion to neutrophil extracellular DNA traps: role in thrombosis

血小板与中性粒细胞胞外 DNA 陷阱的粘附：在血栓形成中的作用

• 批准号: 8105682
• 负责人: DENISA D WAGNER
• 金额: $ 52.88万
• 依托单位: IMMUNE DISEASE INSTITUTE, INC.
• 依托单位国家: 美国
• 财政年份: 2011
• 资助国家: 美国
• 起止时间: 2011-06-15 至 2015-05-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/8105682
• 关键词: Address; Adhesions; Aging; Bacteria; Binding; Biological; Biological Assay; Biological Markers; Blood; Blood Platelets; Cell Adhesion Molecules; Cell Death; Cells; Chromatin; Coagulants; Coagulation Process; DNA; Deep Vein Thrombosis; Deposition; Disease; Disseminated Intravascular Coagulation; Enzymes; Event; Fibrin; Fibrinogen; Fibronectins; Generations; Genetically Engineered Mouse; Growth; Histology; Human; Imaging technology; In Vitro; Inferior vena cava structure; Integrins; Internet; Laboratories; Leukocytes; Ligation; Measures; Mediating; Microbe; Modeling; Molecular; Molecular Target; Mus; Mutant Strains Mice; Operative Surgical Procedures; Pathway interactions; Patients; Plasma; Platelet aggregation; Process; Production; Proteins; Pulmonary Embolism; Recruitment Activity; Role; Sampling; Sepsis; Severities; Specimen; Spiders; Staging; Stenosis; Structure; Thrombocytopenia; Thrombosis; Thrombus; Transfusion; United States; antimicrobial; deep vein; extracellular; genetically modified cells; in vivo; in vivo Model; intravital microscopy; killings; mouse model; neutrophil; receptor; scaffold; thrombolysis

DESCRIPTION (provided by applicant): Neutrophils undergo a cell death pathway that results in release of chromatin coated with antimicrobial proteins forming a web called neutrophil extracellular traps (NETs). NETs trap and kill microbes. Our preliminary results show that NETs recruit and activate platelets. We have evidence of extracellular DNA/chromatin presence in pathological specimens from deep vein thrombosis and in plasma of patients with thrombotic disease. The central hypothesis of this application is that NETs provide a scaffold that, together with fibrin, increases thrombus stability and promotes thrombus growth and microparticle recruitment. We propose that the formation of NETs in pathological circumstances could initiate thrombotic events and contribute to conditions such as sepsis, thrombotic microangiopathies and deep vein thrombosis. In addition, we propose that DNase1, which digests NETs, may modulate thrombosis. We will analyze NETs in the context of in vitro and in vivo models of thrombosis. We will employ a flow chamber with video capability using cells from genetically engineered mice. We propose to study several mouse models of thrombosis, all of which are well established in our laboratory, to visualize NETs formation in vivo with sophisticated imaging technology and study the relevance of NETs to thrombus growth and stability. We are particularly keen to investigate the role of NETs in a new inferior vena cava stenosis model of deep vein thrombosis (DVT) and in a mouse model of sepsis. The proposal has 2 specific aims: 1. To study the molecular mechanisms mediating platelet and microparticle interactions with NETs. To evaluate whether NETs promote fibrin generation. In this Aim, we propose to investigate in vitro the molecular mechanisms involved in platelet adhesion to NETs and address whether NETs promote recruitment of pro-coagulant microparticles (MPs) and fibrin deposition. 2. To study NETs formation in vivo and examine the biological relevance of NETs to sepsis-induced thrombocytopenia and to deep vein thrombosis. To measure NETs biomarkers in samples from patients with thrombosis. In this aim, we propose to visualize NETs by intravital microscopy and by histology. We propose to modulate NETs production and circulating DNA levels and see the effects on murine models of sepsis and DVT. We will study NETs as biomarkers in thrombosis. Thrombosis, including deep vein thrombosis/pulmonary embolism is now the biggest killer in the United States. We hope that our studies will broaden understanding of the thrombotic process in general and that we may uncover new molecular targets to treat pathological thrombosis. PUBLIC HEALTH RELEVANCE: Thrombosis is now the biggest killer in the United States. Thrombi are formed by platelets sticking together. White blood cells influence thrombi formation and their stability. Dying white cells actively release DNA producing large spider web-like structures that trap bacteria. We found that platelets bind to these webs and that such webs are present in thrombi. We propose to investigate the role of this DNA scaffold in thrombosis and the possibility of using enzymes to digest the DNA as a new anti- thrombotic approach.

描述（由申请人提供）：中性粒细胞经历一种细胞死亡途径，导致释放涂有抗微生物蛋白的染色质，形成一种称为中性粒细胞外陷阱（NETS）的网络。净陷阱并杀死微生物。我们的初步结果表明，网将招募和激活血小板。我们有证据表明细胞外DNA/染色质存在于深静脉血栓形成和血栓疾病患者血浆中的病理标本中。该应用的中心假设是网络提供了一个脚手架，该支架与纤维蛋白一起增加了血栓稳定性并促进血栓生长和微粒募集。我们建议，在病理状况下的网络形成可以引发血栓性事件，并有助于败血症，血栓性微动病和深静脉血栓形成等疾病。此外，我们建议消化网的DNASE1可能调节血栓形成。我们将在体外和体内血栓形成模型的背景下分析网。我们将使用基因工程小鼠的细胞采用具有视频能力的流动室。我们建议研究血栓形成的几种小鼠模型，所有这些模型在我们的实验室中均已建立，以使网络中的网络形成具有复杂成像技术的体内，并研究网络与血栓生长和稳定性的相关性。我们特别热衷于研究网络在新的深静脉血栓形成（DVT）的下腔静脉狭窄模型和败血症小鼠模型中的作用。该提案具有2个特定目的：1。研究介导血小板和微粒相互作用的分子机制。 评估网状是否促进纤维蛋白产生。在此目标中，我们建议在体外研究与网络粘附涉及的分子机制，并解决网络是否促进促凝的微粒（MPS）（MPS）和纤维蛋白沉积。 2。在体内研究网络形成，并检查网络与败血症引起的血小板减少症和深静脉血栓形成的生物学相关性。 测量来自血栓形成患者的样品中的生物标志物。在此目标中，我们建议通过插入显微镜和组织学可视化网。我们建议调节网络生产和循环DNA水平，并看到对败血症和DVT鼠模型的影响。我们将研究网络作为血栓形成的生物标志物。血栓形成，包括深静脉血栓形成/肺栓塞，现在是美国最大的杀手。我们希望我们的研究一般来说，我们的研究将扩大对血栓形成过程的了解，并且我们可以发现新的分子靶标以治疗病理血栓形成。 公共卫生相关性：血栓形成现在是美国最大的杀手。血栓是由粘在一起的血小板形成的。白细胞会影响血栓形成及其稳定性。垂死的白细胞积极释放DNA产生大型蜘蛛网样结构，可捕获细菌。我们发现血小板与这些网络结合，并且这种网中存在于血栓中。我们建议研究该DNA支架在血栓形成中的作用，并可能使用酶消化DNA作为一种新的抗血栓形成方法。