Characterization of extracellular inflammasome specks and their vascular effects

细胞外炎性小体斑点的表征及其血管效应

• 批准号: 460752938
• 负责人: Dr. Susanne Gaul
• 金额: --
• 依托单位: Forschungslabor Kardiologie
• 依托单位国家: 德国
• 项目类别: Research Grants
• 资助国家: 德国
• 项目状态: 未结题
• 来源: https://gepris.dfg.de/gepris/projekt/460752938?language=en
• 关键词: Characterization; extracellular; inflammasome; specks; their

Sterile inflammation is involved in the development and progression of atherosclerotic cardiovascular diseases (ASCVD) and represents an interesting novel research field for therapeutic interventions. The NLRP3 inflammasome plays a crucial role in ASCVD as its activation is regulated by exogenous and endogenous stress signals and is associated with the outcome of ASCVD. The NLRP3 inflammasome was originally described as intracellular sensor protein complex that upon its activation it leads to Interleukin-1β secretion and pyroptotic cell death. Thereby, inflammasomes itself can be released into extracellular space. However, the vascular effects of extracellular inflammasome specks and their function during atherogenesis are not yet explored.Our preliminary data revealed that NLRP3 inflammasome activation in human monocytes leads to NLRP3- dependent pyroptotic cell death and release of inflammasome specks into extracellular space. Our findings revealed that extracellular inflammasomes are able to be internalized by surrounding macrophages, human coronary endothelial cells and smooth muscle cells where they exert pro- inflammatory signaling. This led us to the hypothesis that extracellular inflammasomes act as circulating danger signals that perpetuate inflammatory signaling from cell-to-cell and exert pro-atherogenic function. The aim of this project proposal is to investigate the vascular effects of extracellular inflammasomes in-vitro in human coronary endothelial cell and smooth muscle cells and determine whether a blockade of extracellular ASC speck formation and nucleation has beneficial effects on target cells (work package (WP) 1). Further, we will determine whether post-translational modifications (PTMs) of inflammasomes affect assembly, activation and extracellular inflammasome function (WP2). To study whether atherogenesis and pyroptosis in-vivo is dependent on NLRP3 inflammasome activation, we will use inflammasome deficient mice in a Pcsk9-AAV8 induced atherosclerosis model (WP3). And finally, we will explore the clinical association of serum inflammasome levels and pyroptotic cell death of peripheral blood mononuclear cells (PBMCs) in patients with acute myocardial infarct and compare them with healthy controls (WP4).Taken together, these project results will deliver for the first time new insights about the vascular effects of extracellular inflammasomes, their regulation and clinical relevance, and how they drive progression of atherogenesis in-vivo. Our findings will contribute to a novel understanding of inflammasomes as extracellular atherogenic factors and will support the development of innovative therapeutic strategies targeting inflammation in patients with atherosclerotic cardiovascular diseases.

无菌性炎症参与动脉粥样硬化性心血管疾病（ASCVD）的发生和进展，并代表了一个有趣的新的治疗干预研究领域。NLRP 3炎性体在ASCVD中起着至关重要的作用，因为其激活受外源性和内源性应激信号的调节，并且与ASCVD的结果相关。NLRP 3炎性小体最初被描述为细胞内传感器蛋白复合物，其在活化后导致白细胞介素-1 β分泌和焦变性细胞死亡。因此，炎性小体本身可以释放到细胞外空间中。然而，细胞外炎症小体斑点的血管效应及其在动脉粥样硬化形成过程中的功能尚未探索。我们的初步数据显示，NLRP 3炎症小体在人单核细胞中的激活导致NLRP 3依赖性pyroptotic细胞死亡和炎症小体斑点释放到细胞外空间。我们的研究结果表明，细胞外炎性小体能够被周围的巨噬细胞、人冠状动脉内皮细胞和平滑肌细胞内化，在那里它们发挥促炎信号传导。这使我们假设细胞外炎性小体作为循环危险信号，使细胞间的炎症信号传导永久化，并发挥促动脉粥样硬化功能。本项目提案的目的是研究体外人冠状动脉内皮细胞和平滑肌细胞中细胞外炎性小体的血管效应，并确定细胞外ASC斑点形成和成核的阻断是否对靶细胞具有有益作用（工作包（WP）1）。此外，我们将确定炎性小体的翻译后修饰（PTM）是否影响组装，激活和细胞外炎性小体功能（WP 2）。为了研究体内动脉粥样硬化形成和细胞凋亡是否依赖于NLRP 3炎性体活化，我们将在Pcsk 9-AAV 8诱导的动脉粥样硬化模型（WP 3）中使用炎性体缺陷小鼠。最后，我们将探索急性心肌梗死患者血清炎性小体水平与外周血单核细胞（PBMC）的热凋亡细胞死亡的临床相关性，并将其与健康对照组进行比较（WP 4）。总之，这些项目结果将首次提供有关细胞外炎性小体的血管效应，其调节和临床相关性的新见解，以及它们如何在体内推动动脉粥样硬化的进展。我们的研究结果将有助于对炎性小体作为细胞外致动脉粥样硬化因子的新的理解，并将支持开发针对动脉粥样硬化性心血管疾病患者炎症的创新治疗策略。