Bacterial mucin degradation in cystic fibrosis airway disease.

囊性纤维化气道疾病中的细菌粘蛋白降解。

• 批准号: 9398656
• 负责人: Ryan Coulson Hunter
• 金额: $ 37.49万
• 依托单位: UNIVERSITY OF MINNESOTA
• 依托单位国家: 美国
• 财政年份: 2017
• 资助国家: 美国
• 起止时间: 2017-08-01 至 2022-05-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/9398656
• 关键词: Address; Amino Acids; Anaerobic Bacteria; Antibiotic Therapy; Antibiotics; Bacteria; Bacterial Infections; Bioavailable; Carbon; Cell Line; Cells; Chronic; Chronic Obstructive Airway Disease; Chronic Sinusitis; Chronic lung disease; Clinical; Coculture Techniques; Communities; Complex; Coupled; Cystic Fibrosis; Cystic Fibrosis Transmembrane Conductance Regulator; Data; Development; Diet; Disease; Disease Progression; Ecology; Environment; Epithelial Cells; Epithelium; Fermentation; Future; Glycoproteins; Goals; Growth; Health; Hereditary Disease; Histologic; Human; Immunoassay; Impairment; In Vitro; Individual; Infection; Inflammatory Response; Knowledge; Label; Link; Lung; Lung diseases; Metabolic; Modeling; Mucins; Mucous body substance; Mus; Nutrient; Nutritional; Oral; Oral cavity; Organism; Outcome; Pathogenicity; Patients; Population; Prevention; Prevotella; Process; Pseudomonas; Pseudomonas aeruginosa; Pulmonary Cystic Fibrosis; Pulmonary Fibrosis; Respiratory Failure; Respiratory Mucin; Respiratory Tract Infections; Role; Saliva; Site; Source; Sputum; Stable Isotope Labeling; Structure of respiratory epithelium; Symbiosis; Tissues; Translating; Treatment Efficacy; Veillonella; Virulence; base; co-infection; commensal microbes; cystic fibrosis airway; cystic fibrosis patients; density; feeding; improved; in vivo; in vivo imaging system; insight; interdisciplinary approach; microbial; microbiome; microbiota; mortality; novel therapeutic intervention; oral anaerobes; oral bacteria; pathogen; respiratory; salivary mucins; stable isotope; therapeutic development; ventilator-associated pneumonia

PROJECT SUMMARY / ABSTRACT Despite extensive studies of cystic fibrosis (CF) bacterial pathogens, the efficacy of antibiotics achieved in vitro seldom translates to successful clinical outcomes. This limitation is partially driven by our lack of understanding of the host environments to which bacteria adapt, and the metabolic strategies that sustain community growth in vivo. Studies that generate greater insight into what CF pathogens are doing within the cystic fibrosis airways are necessary to inform more effective therapeutic strategies. This proposal addresses how CF pathogens obtain nutrients within the lung. Despite the presence of bacterial cells at high densities, the nutrient source(s) that sustains their growth is not apparent; the predominant carbon reservoir, mucins, are recalcitrant to degradation by the canonical pathogen Pseudomonas aeruginosa. Given their abundance in the lung and their ability to degrade salivary mucins, we propose that anaerobes typically associated with the oral cavity, facilitate carbon acquisition by Pseudomonas, which in turn drives disease. More specifically, commensal bacteria (e.g. Prevotella, Veillonella) are able to thrive off respiratory mucin secretions, releasing mixed fermentation byproducts. We hypothesize that if allowed to accumulate (due to impaired mucus clearance), fermentation-derived metabolites can support the growth of other organisms. We have recently shown that saliva-derived bacterial communities stimulate the growth of P. aeruginosa when provided mucin as the sole carbon source. This suggests that mucin-degrading anaerobes may support pathogens during infection. Based on these data, this project will use a multi-disciplinary approach to (1) identify the anaerobic bacteria and the mucin-derived metabolites they generate that can support P. aeruginosa growth, (2) Use a stable isotope labeling approach to track the flow of mucin-derived carbon throughout CF sputum, (3) Use a mucin-overproducing cell line to assess Pseudomonas-epithelium interactions in the presence of mucin-degrading anaerobes, and (4) use a murine chronic lung infection model to assess the growth and pathogenicity of Pseudomonas in vivo when co-infected with oral-derived anaerobes. At the completion of this study, we will have defined a pathogenic role for oral-associated bacteria in the lower airways and provide a detailed characterization of carbon flow within the CF lung. Altogether, these studies will have a meaningful impact on our understanding of the functional role of the CF microbiota and the potential development of therapeutic strategies. While the CF microbiome will serve as a starting point to investigate mucin-derived cross-feeding interactions, our approach is equally applicable to the prevention of other respiratory diseases – COPD, chronic sinusitis, and ventilator- associated pneumonias – where a viscous mucus environment harbors complex bacterial infections.

项目总结/摘要 尽管对囊性纤维化（CF）细菌病原体进行了广泛的研究，但抗生素的疗效 在体外取得的成果很少转化为成功的临床结果。这一限制部分是由 我们缺乏对细菌适应的宿主环境和代谢策略的了解， 维持群落的生长。对CF病原体有更深入了解的研究 在囊性纤维化气道内进行的研究对于提供更有效的治疗策略是必要的。 该提案涉及CF病原体如何在肺内获得营养。尽管 当细菌细胞以高密度存在时，维持其生长的营养源却不是 明显的;主要的碳库，粘蛋白，是不稳定的降解的典型 病原体铜绿假单胞菌。考虑到它们在肺部的含量和降解能力 唾液粘蛋白，我们提出，厌氧菌通常与口腔，促进碳 被假单胞菌获得，这反过来又驱动疾病。更具体地，肠道细菌（例如， 普雷沃氏菌属、韦荣氏菌属）能够在呼吸道粘蛋白分泌物中茁壮成长， 副产品我们假设，如果允许累积（由于粘液清除受损）， 发酵衍生的代谢物可以支持其他生物体的生长。我们最近的研究表明 唾液来源的细菌群落刺激铜绿假单胞菌的生长时，提供粘蛋白作为 唯一的碳源。这表明粘蛋白降解厌氧菌可能支持病原体， 感染基于这些数据，本项目将采用多学科方法（1）确定 厌氧细菌及其产生的可支持铜绿假单胞菌的粘蛋白衍生代谢物 （2）使用稳定同位素标记方法跟踪整个过程中粘蛋白衍生碳的流动 CF痰液，（3）使用粘蛋白过度产生的细胞系评估假单胞菌-上皮细胞的相互作用， 粘蛋白降解厌氧菌存在，和（4）使用鼠慢性肺感染模型， 评估与口服来源的细菌共感染时假单胞菌在体内的生长和致病性 厌氧菌 在这项研究完成后，我们将确定口腔相关细菌的致病作用 并提供CF肺内碳流的详细表征。总的来说， 这些研究将对我们理解CF的功能作用产生有意义的影响 微生物群和治疗策略的潜在发展。虽然CF微生物组将 作为研究粘蛋白衍生的交叉喂养相互作用的起点，我们的方法同样 适用于预防其他呼吸道疾病- COPD、慢性鼻窦炎和呼吸机- 相关性肺炎-其中粘性粘液环境窝藏复杂的细菌感染。