Neutrophil extracellular traps (NETs) in ventillator induced lung injury

中性粒细胞胞外陷阱（NET）在呼吸机引起的肺损伤中的作用

• 批准号: 9502239
• 负责人: Heather Jones
• 金额: $ 8.75万
• 依托单位: CEDARS-SINAI MEDICAL CENTER
• 依托单位国家: 美国
• 财政年份: 2017
• 资助国家: 美国
• 起止时间: 2017-06-07 至 2019-05-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/9502239
• 关键词: Acute Lung Injury; Adoptive Transfer; Air; Anti-Bacterial Agents; Bacterial Infections; Cell Death Process; Chromatin Fiber; Clinical Treatment; Complex; Complication; DNA; Data; Deposition; Enzyme-Linked Immunosorbent Assay; Extravasation; Future; Generations; Goals; Grant; Growth; Half-Life; Histones; Hypoxemia; Immune; In Vitro; Infection; Infection prevention; Inflammation; Inflammatory; Injury; Innate Immune Response; Intensive Care Units; Invaded; Lead; Life; Lung; Lung infections; Mechanical ventilation; Methods; Modeling; Morphology; Neutrophil Activation; Neutrophil Infiltration; Outcome; Pathology; Patients; Pharmacology; Physiological; Predisposition; Production; Property; Proteins; Pseudomonas aeruginosa; Reporting; Respiratory Failure; Respiratory Therapy; Respiratory physiology; Role; Savings; Source; Sterility; Tidal Volume; Time; Tissues; Trauma; Ventilator-induced lung injury; Work; base; cytokine; design; extracellular; immunoregulation; improved; in vivo; lung injury; mouse model; neutrophil; novel; pathogen; protective effect; respiratory; response; therapeutic target

ABSTRACT Mechanical ventilation (MV) is a life-saving therapy for respiratory failure but also leads to severe physiological and morphological alterations in the lung, known as ventilator-induced lung injury (VILI). Inflammation is a key component of acute lung injury (ALI), and work from our group and others has shown that MV leads to hypoxemia, cytokine production, neutrophil recruitment, and lung injury, even at low tidal volumes. Although neutrophils are most often associated with the pathology of VILI, our proposed study aims to demonstrate a regulatory, tissue-reparative function of neutrophils in the context of VILI and susceptibility to infection. Indeed, the immunomodulatory effects of MV with regards to infection remain unknown. Preliminary data from our lab show that MV stimulates rapid but transient neutrophil recruitment, activation and deposition of extracellular DNA in the airspaces, termed neutrophil extracellular traps (NETs), and we found that these NETs provide protection against infection with Pseudomonas aeruginosa. In particular, this protective effect of neutrophil activity lasts several days after MV, at a time when neutrophils can no longer be detected in the airspaces. Thus, we propose the novel hypothesis that MV-induced neutrophil activation and NET deposition in the airways constitute an innate immune response to tissue damage that counterbalances post-trauma susceptibility to infection. In Specific Aim 1, we will demonstrate that neutrophils are the source of MV-induced NETs using depletion, adoptive transfer and PCR- based methods to detect NET-DNA, as well as quantify the half-life of NETs in the airspaces. Despite the known antibacterial properties of NETs and their induction in response to MV, no study has investigated the impact of NETs on subsequent infection. Thus, in Specific Aim 2, we will experimentally ablate NETs and NET components, both in vivo and in vitro, to determine their impact on bacterial infection of the lung. Thus, using MV as a model of sterile ALI with transient neutrophil extravasation into the air spaces, our work aims to identify an as-yet-unidentified protective effect of NET production and thereby improve the design of future clinical treatments to increase lung function and prevent infection.

摘要 机械通气（MV）是呼吸衰竭的救命疗法，但也会导致严重的呼吸衰竭。 肺的生理和形态学改变，称为呼吸机诱导的肺损伤（VILI）。 炎症是急性肺损伤（ALI）的关键组成部分，我们小组和其他人的工作已经 表明MV导致低氧血症、细胞因子产生、中性粒细胞募集和肺损伤，甚至 在低潮气量下。虽然中性粒细胞最常与VILI的病理学相关，但我们的 这项研究的目的是证明中性粒细胞的调节，组织修复功能， VILI的背景和感染易感性。事实上，MV的免疫调节作用与 感染情况仍不清楚。我们实验室的初步数据显示，MV刺激快速 但短暂的中性粒细胞募集，细胞外DNA的激活和沉积在空气空间中， 称为中性粒细胞胞外陷阱（NET），我们发现这些NET提供保护， 对抗铜绿假单胞菌感染尤其是中性粒细胞的这种保护作用 活动持续数天后，MV，在一个时间时，中性粒细胞不能再检测到在 空域因此，我们提出了新的假设，即MV诱导的中性粒细胞活化和NET 气道中的沉积构成对组织损伤的先天免疫反应， 平衡创伤后感染的易感性。在具体目标1中，我们将展示 中性粒细胞是MV诱导的NET的来源，使用耗竭，过继转移和PCR- 基于检测NET-DNA的方法，以及量化空气空间中NET的半衰期。尽管 NET的已知抗菌特性及其对MV的诱导，没有研究 研究NET对后续感染的影响。因此，在具体目标2中，我们 在体内和体外实验性消融NET和NET组件，以确定其影响 关于肺部细菌感染因此，使用MV作为无菌性ALI伴一过性中性粒细胞减少的模型， 外渗到空气空间，我们的工作旨在确定一个尚未确定的保护作用， NET生产，从而改善未来临床治疗的设计，以增加肺功能 防止感染