Host microbiota and airway mucus: a novel paradigm for lung defense and immune homeostasis during early post-natal development

宿主微生物群和气道粘液：产后早期发育期间肺防御和免疫稳态的新范例

• 批准号: 10305691
• 负责人: Alessandra Maria Livraghi-Butrico
• 金额: $ 38.88万
• 依托单位: UNIV OF NORTH CAROLINA CHAPEL HILL
• 依托单位国家: 美国
• 财政年份: 2020
• 资助国家: 美国
• 起止时间: 2020-02-15 至 2023-11-30
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/10305691
• 关键词: 5 year old; Adult; Affect; Age; Animals; Antibiotic Therapy; Antibiotics; Asthma; Bacterial Infections; Bacterial Pneumonia; Biology; Bronchoalveolar Lavage; Cell Differentiation process; Cells; Child; Congenic Mice; Cystic Fibrosis; Data; Defense Mechanisms; Dehydration; Development; Disease; Elements; Epithelial Cells; Exhibits; Gene Expression; Germ-Free; Harvest; Homeostasis; Human; Immune; Infant; Inflammatory; Inhalation; Knockout Mice; Knowledge; Life; Link; Lung; Lung immune response; MUC5AC gene; Mediating; Messenger RNA; Modeling; Mucins; Mucociliary Clearance; Mucous body substance; Mus; Neonatal; Operative Surgical Procedures; Outcome; Pathogenesis; Pattern; Perinatal; Phenotype; Predisposition; Proteins; Publications; Pulmonary Cystic Fibrosis; Recording of previous events; Respiratory Disease; Respiratory Signs and Symptoms; Respiratory System; Sampling; Secretory Cell; Shapes; Signal Transduction; Surface; Syndrome; System; Testing; Therapeutic; Tube; Wild Type Mouse; age related; biobank; congenic; cystic fibrosis mouse; dysbiosis; early onset; endotracheal; germ free condition; gut dysbiosis; gut microbiota; gut-lung axis; histological specimens; host microbiome; host microbiota; interleukin-22; lung health; lung microbiota; mRNA Expression; mRNA sequencing; mucus clearance; mucus-associated lung diseases; neonatal mice; neonatal period; neonate; novel; pediatric patients; postnatal development; postnatal period; protein expression; rRNA Genes; transcriptome

Airway mucus clearance is a primary lung defense mechanism and the early neonatal period represents a critical “window of susceptibility” for lung health. Perinatal changes in key components of the mucus clearance system have been qualitatively described, but the details and functional significance of these changes are unknown. Our preliminary data in mice and humans indicate that: 1) airway mucus composition is developmentally regulated; and 2) components of the mucus clearance system are affected by the status of the host microbiota in early life. We have identified a testable mechanism to link the host microbiota with neonatal airway mucus biology and lung homeostasis, i.e., the IL-22+ILC3-mediated gut-lung axis. We also posit that humans exhibit age-dependent changes in key elements contributing to airway mucus clearance, e.g., MUC5AC levels. To test these hypotheses, we propose the following aims: 1) To test whether host microbiota dysbiosis or blockade of the IL-22+ILC3-mediated gut-lung axis affect the abundance, composition, and function of airway mucus in neonatal vs. adult mice. Congenic mice raised in germ-free or specific-pathogen free conditions, either naïve or treated with antibiotics, will be assessed at post natal day (PND)10 and PND66 for: 1) bronchoalveolar lavage (BAL) protein composition, mucus concentration, and secreted mucins quantification; 2) airway mucociliary clearance; and 3) lung mRNA sequencing. Specific contributions of IL-22 signaling and outcomes in the context of airway surface dehydration will be assessed using IL-22 KO mice and Scnn1b-Tg mice, respectively. Changes in host microbiota will be determined by bacterial 16S ribosomal RNA gene quantification. 2) To test whether CF-like host microbiota dysbiosis affects the establishment of the normal, IL-22+ILC3-mediated gut-lung axis in neonatal mice. Congenic ∆F508 CF mice and WT littermates, either naïve or treated with antibiotics, will be used at PND10 to study the influx of IL22+ILC3 cells into the lung referenced to quantitative analysis of their gut microbiota. In parallel, lung and BAL samples will be collected to assess the effect of CF gut dysbiosis on the early lung transcriptome and the composition of neonatal airway secretions. Crosses with Scnn1b-Tg mice will be used to exacerbate the ∆F508 CF lung phenotype. 3) To test whether the composition of “healthy” airway mucus presents age- dependent, quantitative differences in humans. Airway mucus samples harvested from endotracheal tubes used in neonates/infants/children (0-5 years old) and adults (25-40 years old) with no history or symptoms of respiratory diseases will be analyzed for mucin and protein composition. Histologic specimens obtained from the LungMAP Biorepository (BRINDL) will be probed for mRNA and protein expression of specific mucus markers. Completion of these aims will establish a new conceptual framework and provide much needed experimental evidence to study the pathogenesis, develop therapeutic approaches, and account for host microbiota influences on “early” lung health and early onset muco-obstructive lung diseases.

气道粘液清除是主要的肺部防御机制和新生儿早期 代表了肺部健康的一个关键“易感性窗口”。围产期主要成分的变化 粘液清除系统已被定性描述，但这些细节和功能意义 变化未知。我们在小鼠和人类中的初步数据表明：1) 气道粘液成分是 发育调节； 2) 粘液清除系统的组成部分受到以下状态的影响 生命早期的宿主微生物群。我们已经确定了一种可测试的机制，将宿主微生物群与 新生儿气道粘液生物学和肺稳态，即 IL-22+ILC3 介导的肠肺轴。我们也 假设人类在有助于呼吸道粘液清除的关键元素上表现出与年龄相关的变化， 例如，MUC5AC 水平。为了检验这些假设，我们提出以下目标：1）检验主机是否 微生物群失调或 IL-22+ILC3 介导的肠肺轴阻断会影响丰度， 新生小鼠与成年小鼠气道粘液的成分和功能。无菌饲养的同类小鼠 或无特定病原体的情况，无论是幼稚的还是用抗生素治疗的，将在出生后当天进行评估 (PND)10 和 PND66 用于：1) 支气管肺泡灌洗液 (BAL) 蛋白质组成、粘液浓度和 分泌粘蛋白定量； 2）气道粘膜纤毛间隙； 3) 肺 mRNA 测序。具体的 将评估 IL-22 信号传导和气道表面脱水情况下的结果的贡献 分别使用 IL-22 KO 小鼠和 Scnn1b-Tg 小鼠。宿主微生物群的变化将由以下因素决定 细菌 16S 核糖体 RNA 基因定量。 2) 测试CF样宿主微生物群是否失调 影响新生小鼠中正常的 IL-22+ILC3 介导的肠肺轴的建立。同类 ΔF508 CF 小鼠和 WT 同窝小鼠，无论是幼稚的还是用抗生素治疗的，都将在 PND10 中用于研究 IL22+ILC3 细胞流入肺部，参考其肠道微生物群的定量分析。与此同时，肺 将收集 BAL 样本以评估 CF 肠道菌群失调对早期肺转录组的影响 新生儿气道分泌物的成分。与 Scnn1b-Tg 小鼠的杂交将用于加剧 ΔF508 CF 肺表型。 3）测试“健康”气道粘液的成分是否代表年龄—— 人类之间依赖的、数量上的差异。从气管内插管采集的气道粘液样本 用于没有病史或症状的新生儿/婴儿/儿童（0-5岁）和成人（25-40岁） 将分析呼吸道疾病的粘蛋白和蛋白质组成。组织学标本取自 肺MAP 生物样本库（BRINDL） 将探测特定粘液的 mRNA 和蛋白质表达 标记。这些目标的完成将建立一个新的概念框架并提供急需的 研究发病机制、开发治疗方法和解释宿主的实验证据 微生物群影响“早期”肺部健康和早发性粘膜阻塞性肺部疾病。