Disordered Proteostasis as a Driver of Disease in the Aging Lung

蛋白质稳态紊乱是衰老肺疾病的驱动因素

• 批准号: 10208506
• 负责人: GR Scott Budinger
• 金额: $ 31.75万
• 依托单位: NORTHWESTERN UNIVERSITY AT CHICAGO
• 依托单位国家: 美国
• 财政年份: 2015
• 资助国家: 美国
• 起止时间: 2015-07-01 至 2025-03-31
• 项目状态: 未结题
• 来源: https://reporter.nih.gov/project-details/10208506
• 关键词: 2019-nCoV; Acute; Address; Adult Respiratory Distress Syndrome; Affect; Aging; Agonist; Alveolar; Alveolar Macrophages; Autopsy; Biological Markers; Biopsy; Blood; Blood Coagulation Factor; Bronchoalveolar Lavage Fluid; C-reactive protein; COVID-19; Cardiovascular system; Cause of Death; Cell Death; Cells; Clinical; Clinical Trials; Coagulation Process; Data; Diffuse; Disease; Disease model; Distant; Elderly; Endothelial Cells; Endothelium; Epithelial Cells; Evaluation; Functional disorder; Genetic Transcription; Heart; Human; Hypotension; Hypoxemia; IL6 gene; Immune; Individual; Infection; Inflammasome; Inflammation; Inflammatory; Influenza A virus; Interleukin-1; Interleukin-6; Intubation; Irrigation; Kidney; Link; Liquid substance; Liver; Lung; Lymphocyte; Macrophage Activation; Mechanical ventilation; Mediating; Modeling; Morbidity - disease rate; Muscle; Organ; Patients; Pneumonia; Primates; Publishing; Reporting; Research Personnel; Respiratory Failure; Rodent; Role; Sampling; Serum; Slice; Source; Spleen; Testing; Therapeutic; Thromboplastin; Thrombosis; Time; Tissue Harvesting; Tissues; Viral; Viral Pneumonia; Virus; Virus Replication; age related; aged; base; cytokine; cytokine release syndrome; experimental study; inhibitor/antagonist; lymph nodes; macrophage; monocyte; mortality; neutrophil; organ injury; prevent; proteostasis; respiratory virus; response; single-cell RNA sequencing; sound; uptake

Pneumonia is the leading cause of death in patients with COVID-19 infection and disproportionately affects older individuals. In addition to the diffuse patchy alveolar infiltrates and acute hypoxemic respiratory failure typical of viral pneumonia, patients with COVID-19 often develop hypotension requiring alpha-adrengergic agonists, very high serum levels of IL-6 and its transcriptional target C-Reactive Protein (CRP) and display evidence of intravascular coagulation. This is accompanied by the death of cells in multiple tissues including the kidney, muscle, liver and occasionally the heart. This end-organ injury is an important driver of morbidity and perhaps mortality in COVID-19 patients. These unusual clinical features suggest a virus-induced cytokine storm, but the underlying mechanisms are unknown and these clinical features are not recapitulated in rodent or primate models of the disease.Our early analysis of bronchoalveolar lavage fluid collected from the alveolar space of patients with severe COVID-19 pneumonia requiring mechanical ventilation challenge the existing paradigm that IL-6 originates in immune cells within the alveolar space. Specifically, we found that at the time of intubation, the alveolar space in the majority of patients with severe COVID-19-induced ARDS harbors mature alveolar macrophages and lymphocytes none of which produce IL-6. Instead, a subset of resident alveolar macrophages produce IL-1? and appear to support replication of SARS-CoV-2.We hypothesize that disordered proteostasis in alveolar macrophages from aged individuals prevents viral killing after uptake of SARS- CoV-2. Replicating virus activates the inflammasome to induce IL-1? release in the lung, which in turn induces the release of IL-6 from endothelial cells in the lung and distant organs. We will test this hypothesis in two related experiments. Experiment 1. To determine whether activation of the inflammasome in response to COVID- 19 infection is necessary for the release of IL-6 from the lung endothelium. We will infect lung slices from normal human donors with SARS-CoV-2 in the presence or absence of an IL-1? inhibitor that is under evaluation as a therapy for patients with COVID-19 associate pneumonia (canakinumab). We will examine the lung slices after infection using single cell RNA-Seq and RNAscope. Experiment 2. To determine whether endothelial cells in tissues outside the lung express IL6 in patients with severe COVID-19. We will perform RNAscope on fixed tissues harvested from 9 patients who have undergone autopsy after COVID-19 at Northwestern and RNAscope plus single cell RNA-Seq on lung, kidney, spleen and lymph nodes from 5 patients who undergo post- mortem biopsy in our ICU.

肺炎是COVID-19感染患者死亡的主要原因，对老年人的影响不成比例 个体除了弥漫性斑片状肺泡浸润和典型的急性低氧性呼吸衰竭， 病毒性肺炎，COVID-19患者经常发生低血压，需要α-肾上腺素能受体激动剂， IL-6及其转录靶点C-反应蛋白（CRP）血清水平升高， 血管内凝血这伴随着包括肾脏在内的多种组织中的细胞死亡， 肌肉肝脏偶尔还有心脏这种终末器官损伤是发病率的重要驱动因素， COVID-19患者的死亡率。这些不寻常的临床特征表明病毒诱导的细胞因子风暴，但 潜在的机制尚不清楚，这些临床特征在啮齿动物或灵长类动物中未重现 我们早期分析了从哮喘患者的肺泡腔收集的支气管肺泡灌洗液， 需要机械通气的严重COVID-19肺炎患者挑战了现有的范式， IL-6来源于肺泡腔内的免疫细胞。具体来说，我们发现在插管时， 大多数严重COVID-19诱导的ARDS患者的肺泡腔含有成熟的肺泡 巨噬细胞和淋巴细胞都不产生IL-6。相反，一部分肺泡巨噬细胞 产生IL-1？并且似乎支持SARS-CoV-2的复制。我们假设， 老年人肺泡巨噬细胞的蛋白质稳态阻止了SARS病毒的杀伤作用- 二型冠状病毒复制病毒激活炎性小体诱导IL-1？在肺中释放，这反过来又诱导 肺和远端器官内皮细胞释放IL-6。我们将在两个相关的实验中验证这一假设。 实验实验1.为了确定炎症小体的激活是否响应于COVID-19， 19感染对于从肺内皮释放IL-6是必需的。我们将感染来自 正常人捐助者与SARS-CoV-2的存在或不存在的IL-1？正在评估的抑制剂 作为COVID-19相关肺炎患者的治疗（卡那单抗）。我们会检查肺部切片 感染后使用单细胞RNA-Seq和RNAscope。实验2.为了确定内皮细胞是否 在严重的COVID-19患者中，肺外组织中的细胞表达IL 6。我们将执行RNAscope 从9名在西北大学接受COVID-19尸检的患者身上采集的固定组织， RNAscope加单细胞RNA-Seq对来自5名患者的肺、肾、脾和淋巴结的研究， 尸检活组织检查