Testing the hypothesis that microbial energetic hijacking of the CF immune response selects for specific pathogens during lung function decline

检验以下假设：CF 免疫反应的微生物能量劫持会在肺功能下降期间选择特定病原体

• 批准号: 10618780
• 负责人: Dianne K Newman
• 金额: $ 45.29万
• 依托单位: CALIFORNIA INSTITUTE OF TECHNOLOGY
• 依托单位国家: 美国
• 财政年份: 2020
• 资助国家: 美国
• 起止时间: 2020-06-01 至 2024-04-30
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/10618780
• 关键词: Adult; Antibiotics; Automobile Driving; Bacteria; Bacterial Physiology; Carbon; Cell Respiration; Charge; Chronic; Complex; Consumption; Cystic Fibrosis; Cystic Fibrosis sputum; Disease Progression; Dissection; Drug Design; Drug Metabolic Detoxication; Earth science; Energy-Generating Resources; Environment; Enzymes; Epithelial Cells; Fingerprint; Floods; Forensic Medicine; Gases; Gene Expression; Generations; Genes; Genetic; Growth; Habitats; Health; Human; Hypoxia; Image; Immune response; Immune system; In Vitro; Individual; Inflammatory; Isotopes; Knowledge; Learning; Lung infections; Mass Spectrum Analysis; Measurable; Measurement; Measures; Membrane; Metabolic; Metabolism; Microbe; Microbial Biofilms; Molecular Profiling; Morbidity - disease rate; Mucous body substance; Nitric Oxide; Nitrous Oxide; Oxidants; Oxides; Oxygen; Pathway interactions; Patients; Pattern; Physiological; Pilot Projects; Process; Production; Pulmonary Cystic Fibrosis; Respiratory Process; Respiratory Tract Infections; Role; Site; Soil; Source; Sputum; System; Testing; Tobramycin; antibiotic tolerance; cohort; combat; cystic fibrosis airway; cystic fibrosis infection; cystic fibrosis patients; denitrification; dysbiosis; experimental study; fitness; fungus; host-microbe interactions; in situ imaging; in vivo; innovation; insight; lung failure; member; microbial; microbial community; microbiome; microbiota; model organism; mortality; neutrophil; novel; opportunistic pathogen; oxidation; pathogen; pulmonary function decline; stable isotope; tool; trait; translational approach

PROJECT SUMMARY Individuals living with cystic fibrosis (CF) combat devastating, chronic microbial infections of the airways. Though CF patients are usually colonized by otherwise innocent bacteria and fungi—many of which derive from soil environments—the compromised CF immune system is unable to clear these opportunists, and the ensuing struggle between host and microbes eventually leads to failure of the pulmonary system. Conventional antibiotics are not very effective. One widely held view for why this is the case is that the resident microbiota are growing slowly and their membranes are insufficiently charged to take up commonly-used antibiotics such as tobramycin. Accordingly, if we seek new ways to treat CF lung infections, we must better understand how microbes thrive in this habitat. Different lines of evidence indicate that oxygen is limiting in the CF airways at the microscale relevant to opportunistic pathogens. Though carbon sources are replete in the mucus-filled airways, in the absence of oxygen, the bacteria and fungi that come to dominant this habitat must employ alternative energy generation strategies to aerobic respiration. How do they do this? Energy flow is the driving organizer of any microbial community, including those found in the CF airways. It is well established that the nitric oxide (NO) generated by the immune system in the CF patients is lower than that made by healthy individuals. Indeed, epithelial cells are severely compromised in NO production, yet neutrophils that flood the CF airways can still generate NO; this NO is insufficient to kill the microbes, but has the potential to transform into an energy source for those capable of denitrification. Accordingly, we seek to test the hypothesis that microbial energetic hijacking of the CF immune response via denitrification pathways selects for specific pathogens during lung function decline. To test this hypothesis, we plan to leverage powerful isotopic tools from the Earth sciences that permit the sources of metabolites in complex environments, such as the CF airways, to be determined atom by atom, providing a non-invasive, forensic molecular fingerprint. In particular, we will focus on interpreting N2O, a measurable product of the denitrification pathway in CF sputum and breath gas. In addition to approaches employing bacterial physiology, genetics, and in situ imaging of host-microbe interactions, we will use these isotopic tools to gain insight into how the NO that is reduced to N2O in the CF airways may favor the fitness of particular microbial community members. To do this, we propose three specific aims: Aim 1 will identify the conditions and pathways leading to N2O production by common CF bacteria and fungi, Aim 2 will utilize advanced isotopic analyses to dissect the N2O produced by these microbes to forensically infer its source, and Aim 3 will apply these insights to a pilot study of adult CF patients to determine whether particular types of denitrifiers are favored as lung function declines. Attainment of these objectives will provide the critical knowledge needed to guide early translational approaches for treating infections of the CF airways, as well as establish tools that can be applied more broadly to other studies of dysbiosis.

项目概要 囊性纤维化 (CF) 患者正在对抗毁灭性的慢性气道微生物感染。 尽管囊性纤维化患者通常被其他无害的细菌和真菌定殖——其中许多源自 来自土壤环境——受损的 CF 免疫系统无法清除这些机会主义者，并且 宿主和微生物之间随之而来的斗争最终导致肺部系统的衰竭。 对于为什么会出现这种情况，一种广泛持有的观点是，抗生素并不是很有效。 生长缓慢，它们的膜没有足够的电荷来吸收常用的抗生素，例如 因此，如果我们寻求治疗 CF 肺部感染的新方法，我们必须更好地了解如何治疗。 不同的证据表明，CF 气道中的氧气受到限制。 尽管充满粘液的碳源充足，但与机会性病原体相关的微观尺度。 呼吸道，在没有氧气的情况下，在这个栖息地占主导地位的细菌和真菌必须利用 有氧呼吸的替代能源产生策略 他们是如何做到这一点的？ 任何微生物群落的组织者，包括 CF 气道中发现的微生物群落。 CF 患者免疫系统产生的一氧化氮 (NO) 低于健康人 事实上，上皮细胞的一氧化氮生成严重受损，但中性粒细胞却大量涌入。 CF气道仍然可以产生NO；这种NO不足以杀死微生物，但具有转化的潜力 因此，我们试图检验以下假设： 微生物通过反硝化途径对 CF 免疫反应进行能量劫持，选择特定的 为了检验这一假设，我们计划利用强大的同位素工具。 来自地球科学，允许复杂环境中代谢物的来源，例如 CF 气道，逐个原子地确定，提供非侵入性的法医分子指纹。 我们将重点解释 N2O，它是 CF 痰液和呼吸中反硝化途径的可测量产物 除了采用细菌生理学、遗传学和宿主微生物原位成像的方法之外。 相互作用，我们将使用这些同位素工具来深入了解 CF 中的 NO 如何还原为 N2O 呼吸道可能有利于特定微生物群落成员的健康为了做到这一点，我们提出了三个具体的建议。 目标：目标 1 将确定常见 CF 细菌产生 N2O 的条件和途径，以及 真菌，Aim 2 将利用先进的同位素分析来剖析这些微生物产生的 N2O，以 通过法医推断其来源，Aim 3 将把这些见解应用于成人 CF 患者的试点研究中，以确定 当肺功能下降时，特定类型的反硝化剂是否会受到青睐。 提供指导治疗 CF 感染的早期转化方法所需的关键知识 气道，以及建立可以更广泛地应用于其他生态失调研究的工具。