SELECTIVE DELETION OF NEUTROPHIL NADPH OXIDASE AND INNATE RESPONSES TO ASPERGILLUS FUMIGATUS

中性粒细胞 NADPH 氧化酶的选择性缺失和对烟曲霉的先天反应

基本信息

批准号：
9368526
负责人：
Mary C Dinauer
金额：
$ 38.13万
依托单位：
WASHINGTON UNIVERSITY
依托单位国家：
美国
项目类别：
财政年份：
2017
资助国家：
美国
起止时间：
2017-08-09 至 2021-06-30
项目状态：
已结题

来源：
https://reporter.nih.gov/project-details/9368526
关键词：
Abscess Address Affect Alveolar Alveolar Macrophages Antifungal Agents Aspergillosis Aspergillus Aspergillus fumigatus Attenuated Bacterial Infections Breathing Cell Wall Cells Chemotactic Factors Chronic Granulomatous Disease Complication Data Disease Dose Enzymes Exhibits Failure Gene Targeting Genetic Genetically Engineered Mouse Goals Granulomatous Heritability Hour Human Hyphae Immune Immune response Immunity Immunologic Deficiency Syndromes Impairment In Vitro Infection Infiltration Inflammation Inflammation Mediators Inflammatory Inflammatory Response Inherited Knockout Mice Leukocytes Life Lung Mediating Mediator of activation protein Molds Molecular Mus Mutation Mycoses Myeloid Cells NADPH Oxidase Natural Immunity Opportunistic Infections Oxidants Oxidases Pathway interactions Patients Pattern Phagocytes Pharmaceutical Preparations Phenotype Play Pneumonia Production Reactive Oxygen Species Recurrence Reporting Reproduction spores Residual state Resistance Risk Role S100A8 gene Source Sterility Surface Transgenes Transgenic Organisms Wild Type Mouse Work chemotherapy cytokine improved in vivo insight killings macrophage microbicide monocyte mouse model neutrophil novel novel therapeutic intervention pathogen patient population prevent receptor response restoration superoxide-generating NADPH oxidase translational impact

项目摘要

Summary Pneumonia resulting from inhaling spores of the opportunistic mold Aspergillus fumigatus (AF) remains a life- threatening complication of chronic granulomatous disease (CGD) and other conditions with compromised innate antifungal immunity. CGD is a heritable immunodeficiency arising from inactivating mutations in the phagocyte NADPH oxidase that generates superoxide (O2-).1, 2 Lack of microbicidal O2--derived reactive oxygen species (ROS) leads to recurrent bacterial and fungal infections. CGD patients are also prone to excessive and detrimental inflammation. Aspergillus pneumonia in CGD is associated with pyogranulomatous inflammation that complicates treatment. After conidia are inhaled, host receptors for fungal pathogen- associated molecular patterns (PAMPs) trigger inflammatory mediator production and activate killing by macrophages, neutrophils (polymorphonuclear leukocytes, PMN) and other leukocytes, which rapidly eliminates AF from normal hosts. Failure to do so results in AF pneumonia. Although patients with CGD and mice genetically engineered with similar mutations (CGD mice) are among the most susceptible, our understanding of how NADPH oxidase ROS control AF and its associated inflammation in the lung are ill- defined. To address this question, we developed new mouse models in which the NADPH oxidase is selectively deleted in PMN or resident lung alveolar macrophages (AM). Our preliminary data show that mice lacking only PMN NADPH oxidase ROS exhibited a phenotype similar to CGD mice, and were susceptible to both AF pneumonia and hyperinflammation following challenge with sterile fungal cell walls, despite intact NADPH oxidase activity in other cells. In contrast, mice lacking NADPH oxidase in AM, but with residual oxidase activity in most PMN and monocytes, resembled WT mice in these studies. We propose to determine how the PMN NADPH oxidase is crucial in the early innate responses to AF, including an unexplained role in regulating fungal PAMP-induced inflammation. In Aim 1, we will assess whether PMN ROS play a non- redundant role in the initial response to AF that is critical to prevent lung infection, although it is possible that other sources of oxidase ROS or non-oxidative mechanisms could suffice at low inocula. In Aim 2, we will determine how PMN NADPH oxidase regulates fungal PAMP-induced inflammation. We hypothesize that lack of PMN ROS leads to excessive release inflammatory cytokines, including PMN chemoattractants produced by PMN themselves. We will examine the response of oxidase-deficient PMN to sterile fungal PAMPs both in vitro and in the lung to determine how loss of PMN ROS exacerbates inflammation independent of active infection. We will investigate the impact of blocking specific inflammatory mediators after fungal cell wall challenge. If effective, we will evaluate this approach in CGD mice as a means to reduce excessive inflammation and improve control of AF. The proposed studies will provide novel insights into incompletely characterized factors that contribute to life-threatening infection with AF and guide new therapeutic strategies.

概括肺炎是由机会性霉菌烟曲霉（AF）吸入孢子引起的威胁慢性肉芽肿性疾病（CGD）和其他疾病的威胁并发症先天抗真菌免疫。 CGD是一种可遗传的免疫缺陷，是由于失活突变引起的产生超氧化物（O2-）的吞噬细胞NADPH氧化酶。1，2缺乏微生物O2的反应性反应性氧（ROS）导致复发细菌和真菌感染。 CGD患者也很容易过度和有害的炎症。 CGD中肺炎的曲霉与Pyogranulomatos有关炎症使治疗复杂化。吸入分生孢子后，用于真菌病原体的宿主受体相关的分子模式（PAMP）触发炎症介质产生并激活杀戮巨噬细胞，中性粒细胞（多形核白细胞，PMN）和其他白细胞，它们迅速从普通宿主中消除AF。不这样做会导致AF肺炎。虽然患有CGD的患者和用类似突变（CGD小鼠）进行基因工程的小鼠是最易感的，我们了解NADPH氧化酶ROS控制AF及其在肺中的相关炎症如何不良定义。为了解决这个问题，我们开发了NADPH氧化酶的新鼠标模型在PMN或常驻肺肺泡巨噬细胞（AM）中有选择地删除。我们的初步数据表明小鼠仅缺乏PMN NADPH氧化酶ROS表现出类似于CGD小鼠的表型，并且容易受到影响尽管完好无损其他细胞中的NADPH氧化酶活性。相反，AM中缺乏NADPH氧化酶的小鼠，但残留在这些研究中，大多数PMN和单核细胞中的氧化酶活性，类似于WT小鼠。我们建议确定 PMN NADPH氧化酶在早期对AF的先天反应中至关重要，包括无法解释的作用调节真菌PAMP引起的炎症。在AIM 1中，我们将评估PMN ROS是否发挥非 - 在对AF的最初反应中的冗余作用，这对于防止肺部感染至关重要，尽管有可能氧化酶ROS或非氧化机制的其他来源在低接种物中就足够了。在AIM 2中，我们将确定PMN NADPH氧化酶如何调节真菌PAMP诱导的炎症。我们假设缺乏 PMN ROS导致过度释放炎性细胞因子，包括由 PMN本身。我们将在体外检查氧化酶缺陷PMN对无菌真菌疫苗的反应并在肺中确定PMN ROS的丧失如何加剧炎症独立于主动感染。我们将研究真菌细胞壁挑战后阻止特定炎症介质的影响。如果有效，我们将在CGD小鼠中评估这种方法，以减少过度炎症和改善对AF的控制。拟议的研究将为未完全表征因素提供新的见解这有助于使用AF并指导新的治疗策略威胁生命的感染。