A critical role for macrophage ferroptosis in promoting fungal invasion in lung transplant recipients

巨噬细胞铁死亡在促进肺移植受者真菌侵袭中的关键作用

• 批准号: 10186399
• 负责人: Joe L Hsu
• 金额: $ 59.3万
• 依托单位: STANFORD UNIVERSITY
• 依托单位国家: 美国
• 财政年份: 2021
• 资助国家: 美国
• 起止时间: 2021-04-01 至 2026-03-31
• 项目状态: 未结题
• 来源: https://reporter.nih.gov/project-details/10186399
• 关键词: Acute; Acute Renal Failure with Renal Papillary Necrosis; Address; Adult Respiratory Distress Syndrome; Affect; Alveolar; Alveolar Macrophages; Alzheimer' s Disease; Animals; Aspergillosis; Aspergillus; Aspergillus fumigatus; Atherosclerosis; Biology; Bronchoalveolar Lavage; Cell Culture Techniques; Cell Death; Chronic Obstructive Airway Disease; Clinical; Control Animal; Cytometry; Defect; Discrimination; Effector Cell; Exposure to; Flow Cytometry; Fluorescence; Fluorescence-Activated Cell Sorting; Genes; Graft Rejection; Granulocyte-Macrophage Colony-Stimulating Factor; Hemorrhage; Histopathologic Grade; Homeostasis; Homologous Transplantation; Host Defense; Human; Immune; Immunity; In Vitro; Infection; Inflammatory; Ingestion; Innate Immune Response; Iron; Iron Chelating Agents; Iron Overload; Label; Laboratories; Life; Lipid Peroxides; Lipids; Lung Transplantation; Lung diseases; Macrophage Colony-Stimulating Factor; Malignant Neoplasms; Mass Spectrum Analysis; Measures; Mediating; Microscopy; Molds; Morbidity - disease rate; Mus; Mycoses; Oranges; Oxidation-Reduction; Parkinson Disease; Pathogenesis; Peptide Hydrolases; Pharmaceutical Preparations; Phenotype; Procedures; Production; Protease Inhibitor; Reactive Oxygen Species; Reperfusion Injury; Reporter; Reproduction spores; Role; Savings; Statistical Methods; Techniques; Testing; Time; Tissues; Trachea; Transgenic Mice; Transplant Recipients; Transplantation; Viral Pneumonia; Western Blotting; clinically actionable; design; emerging pathogen; experimental study; improved outcome; in vivo; inhibitor/antagonist; macrophage; monocyte; mortality; nanoparticle; neutrophil; novel; novel therapeutic intervention; pathogen; post-transplant; protease E; response; response to injury; transplant model

PROJECT SUMMARY/ ABSTRACT This application focuses on the contribution of transplant hemorrhage-induced iron overload in the dysregulation of pulmonary macrophages (mɸs) and the promotion of invasive aspergillosis. Aspergillus fumigatus (Af) is a ubiquitous mold that releases airborne spores (conidia) and affects nearly 20 million people worldwide. One-in- three lung transplant recipients (LTRs) suffers from Aspergillus-related pulmonary disease. While lung transplantation can be a life-saving treatment for thousands of people, survival post-transplant is often limited by Af infection. To better understand the transplant (host)-Af (pathogen) relationship, we developed a murine orthotopic tracheal transplant (OTT) model of Af infection. We have shown that transplant rejection-mediated microhemorrhage increases tissue iron levels and determines Af invasion. However, the exact interaction between immunity, iron overload and infection are still poorly understood. Mɸs are the first line of defense against Af and are also central to restoring tissue iron homeostasis. Importantly, our preliminary results indicate that microhemorrhage-mediated iron overload: (i) profoundly impacts the ability of mfs to kill Af conidia through a defect in lysosomal acidification; (ii) the innate immune response is polarized toward a pro-inflammatory mɸs state that results in high levels of tissue damaging reactive oxygen species (ROS); and (iii) iron promotes mɸ ferroptosis. Ferroptosis is a newly recognized form of regulated cell death that results from the production of iron toxic lipid ROS. Ferroptosis was first recognized in cancer but is now known to contribute to Alzheimer’s and Parkinson’s disease, ischemia reperfusion injury, atherosclerosis, acute kidney injury and the response to acute hemorrhage. However, the role of ferroptosis in lowering the host’s defense against pathogens, if any, remains unknown. The proposed studies are designed to address these questions in terms of Af invasion. The central hypothesis is that transplant microhemorrhage-mediated iron overload induces mf ferroptosis and polarization into an unrestrained pro-inflammatory phenotype that promotes Af invasion. Specific aim 1 utilizes in vitro and in vivo experiments to investigate the concept that ferroptosis is dictated by mɸs polarization state and contributes to the inability of transplant mɸs to mitigate Af infection and studies the role of iron lowering agents and anti-ferroptotic drugs to decrease fungal invasion. Specific aim 2 uses state-of-art omics techniques to define iron induced Af proteases and tests the concept that fungal protease inhibition can mitigate ferroptosis and improve outcomes in the tracheal transplant model. Specific aim 3 studies the ability of alveolar mɸs isolated from human LTRs compared to non-lung transplants to kill Af conidia and correlates the ability of mɸs to kill conidia with mɸs-polarization state and ferroptosis, using mass cytometry. This aim will provide a direct translatability of the hypothesis that iron overload induces ferroptosis and a pro-inflammatory phenotype that promotes fungal invasion. Successful completion of these studies will allow for the discovery of a fundamental new biology and provide novel targets for the treatment of fungal infections.

项目概要/摘要 本申请重点关注移植出血引起的铁过载在失调中的作用 肺巨噬细胞（mɸs）的减少和侵袭性曲霉病的促进。烟曲霉 (Af) 是一种 无处不在的霉菌，会释放空气中的孢子（分生孢子），影响全世界近 2000 万人。一合一- 三名肺移植受者 (LTR) 患有曲霉相关肺部疾病。而肺 移植可以成为成千上万人的挽救生命的治疗方法，但移植后的生存往往受到以下因素的限制 AF感染。为了更好地了解移植物（宿主）-Af（病原体）关系，我们开发了一种小鼠 Af感染的原位气管移植（OTT）模型。我们已经证明移植排斥介导 微出血增加组织铁水平并决定房颤侵袭。然而，确切的相互作用 免疫、铁过载和感染之间的关系仍然知之甚少。 Mɸs 是防御的第一道防线 Af 和 也是恢复组织铁稳态的核心。重要的是，我们的初步结果表明 微出血介导的铁超载：(i) 深刻影响 mfs 通过 af 杀死分生孢子的能力 溶酶体酸化缺陷； (ii) 先天免疫反应极化为促炎性 mɸs 导致高水平的组织损伤性活性氧 (ROS) 状态； (iii) 铁促进 mɸ 铁死亡。铁死亡是一种新认识的受调节细胞死亡形式，由铁的产生引起 有毒脂质ROS。铁死亡首先在癌症中被发现，但现在已知会导致阿尔茨海默病和 帕金森病、缺血再灌注损伤、动脉粥样硬化、急性肾损伤以及急性肾损伤的反应 出血。然而，铁死亡在降低宿主对病原体的防御能力方面的作用（如果有的话）仍然存在 未知。拟议的研究旨在解决房颤入侵方面的这些问题。中央 假设是移植微出血介导的铁过载诱导中频铁死亡和极化 转化为不受限制的促炎表型，促进房颤侵袭。具体目标 1 利用体外和 体内实验研究铁死亡是由 mɸs 极化状态决定的概念 导致移植 mɸs 无法减轻房颤感染，并研究降铁剂的作用 和抗铁死亡药物以减少真菌侵袭。具体目标 2 使用最先进的组学技术来定义 铁诱导 Af 蛋白酶并测试真菌蛋白酶抑制可以减轻铁死亡和 改善气管移植模型的结果。具体目标3研究肺泡mɸs分离的能力 与非肺移植相比，人类 LTR 杀死 Af 分生孢子的能力，并将 mɸs 杀死的能力关联起来 使用质谱流式细胞仪观察具有 mɸs 极化状态和铁死亡的分生孢子。这一目标将直接提供 铁过载会导致铁死亡和促炎表型这一假设的可翻译性 促进真菌入侵。成功完成这些研究将有助于发现一个基本的 新生物学并为治疗真菌感染提供新靶点。