Human Airway Colonization by Mycoplasma pneumoniae

肺炎支原体在人呼吸道定植

• 批准号: 9058484
• 负责人: DUNCAN C KRAUSE
• 金额: $ 38.91万
• 依托单位: UNIVERSITY OF GEORGIA
• 依托单位国家: 美国
• 财政年份: 2014
• 资助国家: 美国
• 起止时间: 2014-05-15 至 2019-04-30
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/9058484
• 关键词: Accounting; Address; Adherence; Air; Asthma; Atomic Force Microscopy; Bacterial Adhesins; Binding; Carbohydrates; Cells; Characteristics; Chemotaxis; Child; Chronic; Chronic Obstructive Airway Disease; Cilia; Communities; Complement Receptor; Data; Electrons; Environment; Epithelial Cells; Event; Gel; Glycoproteins; Glycosphingolipids; Goals; Health; Histocytochemistry; Hospitalization; Human; Immune; In Vitro; Incidence; Infection; Inorganic Sulfates; Knowledge; Label; Lectin; Life; Link; Liquid substance; Lung diseases; Mediating; Modeling; Molecular; Monoclonal Antibodies; Mucins; Mycoplasma; Mycoplasma pneumoniae; Nature; Organelles; Outcome; Pathogenesis; Pattern; Phenotype; Pneumonia; Polysaccharides; Population; Preparation; Process; Proteins; Publishing; Sialic Acids; Sialoglycoproteins; Source; Specificity; Structure; Sulfoglycosphingolipids; Surface; Testing; Tissue Sample; Tissues; Unspecified or Sulfate Ion Sulfates; Work; airway epithelium; base; cell motility; density; glycolipid receptor; human tissue; interest; molecular recognition; pathogen; receptor; receptor binding; respiratory; screening; sulfoglycolipids; tissue tropism; transmission process; young adult

DESCRIPTION (provided by applicant): Mycoplasma pneumoniae is a major cause of community-acquired respiratory disease, accounting for >20% of all pneumonia and >100,000 hospitalizations annually in the U.S., and is the leading cause of pneumonia in older children and young adults. Infections are often chronic and can precipitate or exacerbate life-altering conditions including asthma and COPD, but the molecular basis for tissue tropism and persistence in the airways is not known. Mycoplasma adhesin protein P1 functions directly in receptor binding and gliding motility. Sialoglycoproteins and sulfated glycolipids such as sulfatide have been identified as receptors, but M. pneumoniae cells glide when bound to sialoglycoproteins and are static when bound to sulfatide. Our long- term goal is to understand how the dynamic interplay between M. pneumoniae and airway epithelium impacts transmission, tissue tropism, within-host spread, immune evasion, and persistence. A greater understanding of the underlying molecular recognition events and how they impact infection outcome will enhance our ability to develop new strategies to limit incidence and impact. Our central hypothesis is that M. pneumoniae adherence and gliding motility are influenced by the density and structure of airway glycans, which in turn impacts colonization pattern and within-host spread. Surprisingly little is known about the structure and distribution of airway glycans, despite their fundamental importance for diverse respiratory pathogens. Aim 1 will characterize the human airway glycome in the context of potential M. pneumoniae receptors, addressing which glycans are found where and at what levels in a human airway model and in human airway tissues. We will utilize state-of- the-art carbohydrate structural analysis to define the glycome of normal human bronchial epithelial (NHBE) cells grown in air-liquid interface culture, with which we model mycoplasma colonization. We speculate that glycan environment contributes to the distinct spatial and temporal colonization patterns observed in this model. Results from NHBE cell glycome analysis will be compared with comprehensive sulfated glycolipid analysis of human tissue samples from upper and lower airways. Aim 2 will define M. pneumoniae binding specificity and force and gliding phenotype on receptor populations, addressing which potential receptors impact binding and gliding activity. We will screen a comprehensive glycan array to determine binding specificity, determine binding strength by atomic force microscopy, and evaluate adherence and gliding on sialoglycoprotein and sulfated glycolipid receptor moieties individually and in combination at different relative concentrations. Aim 3 will characterize a subpopulation of the adhesin P1 protein that is defined by its characteristic monoclonal antibody labeling pattern, assess how changes in the abundance of this P1 subpopulation correlate with adherence and gliding function, and correlate P1 dynamics with structural changes on the terminal organelle surface, as observed by electron cryotomography.

描述（由申请人提供）：肺炎支原体是社区获得性呼吸道疾病的主要原因，在美国占所有肺炎的 20% 以上，每年住院人数超过 100,000 例，并且是年龄较大儿童和年轻人肺炎的主要原因。感染通常是慢性的，可以引发或加剧改变生活的疾病，包括哮喘和慢性阻塞性肺病，但组织向性和气道持续存在的分子基础尚不清楚。支原体粘附蛋白 P1 直接在受体结合和滑动运动中发挥作用。唾液酸糖蛋白和硫酸化糖脂如硫苷脂已被鉴定为受体，但肺炎支原体细胞在与唾液酸糖蛋白结合时滑动，在与硫苷脂结合时静止。我们的长期目标是了解肺炎支原体和气道上皮之间的动态相互作用如何影响传播、组织向性、宿主内传播、免疫逃避和持久性。更好地了解潜在的分子识别事件以及它们如何影响感染结果将增强我们制定新策略来限制发病率和影响的能力。我们的中心假设是肺炎支原体的粘附和滑动运动受到气道聚糖的密度和结构的影响，这反过来又影响定植模式和宿主内的传播。令人惊讶的是，人们对气道聚糖的结构和分布知之甚少，尽管它们对于多种呼吸道病原体至关重要。目标 1 将在潜在肺炎支原体受体的背景下描述人类气道糖组的特征，解决在人类气道模型和人类气道组织中发现哪些聚糖的位置和水平。我们将利用最先进的碳水化合物结构分析来定义在气液界面培养物中生长的正常人支气管上皮（NHBE）细胞的糖组，并用其模拟支原体定植。我们推测聚糖环境有助于在该模型中观察到的独特的空间和时间定植模式。 NHBE 细胞糖组分析的结果将与上呼吸道和下呼吸道人体组织样本的硫酸化糖脂综合分析结果进行比较。目标 2 将定义肺炎支原体对受体群体的结合特异性以及力和滑动表型，解决哪些潜在受体影响结合和滑动活性。我们将筛选全面的聚糖阵列以确定结合特异性，通过原子力显微镜确定结合强度，并评估唾液酸糖蛋白和硫酸化糖脂受体部分在不同相对浓度下单独和组合的粘附和滑动。目标 3 将表征由其特征性单克隆抗体标记模式定义的粘附素 P1 蛋白亚群，评估该 P1 亚群丰度变化如何与粘附和滑动功能相关，并将 P1 动态与末端细胞器表面的结构变化相关联，如电子冷冻断层扫描所观察到的。