Evaluating Mycobacterium avium glycopeptidolipids as key factors in the transition from biofilm to macrophages

评估鸟分枝杆菌糖肽脂作为从生物膜向巨噬细胞转变的关键因素

基本信息

批准号：
10582714
负责人：
JEFFREY Scott SCHOREY
金额：
$ 19.56万
依托单位：
UNIVERSITY OF NOTRE DAME
依托单位国家：
美国
项目类别：
财政年份：
2022
资助国家：
美国
起止时间：
2022-03-02 至 2025-02-28
项目状态：
未结题

来源：
https://reporter.nih.gov/project-details/10582714
关键词：
Address Anabolism Antibiotic Therapy Antibiotics Bacillus Bacteria Biological Biology Cell surface Cells Chronic lung disease Clinical Data Diagnosis Disease Elderly Engineering Environment Gene Expression Genes Genetic Genetic Transcription Genus Mycobacterium Goals Growth Guidelines Habitats Household Human Immune Individual Infection Invaded Knowledge Life Style Lung Lung diseases Macrophage Macrophage Activation Microbe Microbial Biofilms Modification Mycobacterium avium Mycobacterium avium Complex Mycobacterium avium-intracellulare Infection Mycobacterium tuberculosis Opportunistic Infections Organism Pathogenesis Patients Pattern recognition receptor Phagocytosis Phagosomes Phenotype Play Plumbing Principal Investigator Process Relapse Respiratory Disease Role Slide Soil Source Sputum Structure Surface System Testing Therapeutic United States Variant cell motility common treatment differential expression knockout gene lung injury mutant non-tuberculosis mycobacteria pathogen patient population programs recurrent infection stressor success transcriptome transmission process

项目摘要

Project summary Non-tuberculosis mycobacteria like M. avium are widespread environmental organisms, occurring in many habitats, both natural and engineered (). The ability of M. avium to colonize household plumbing, hot tubs, and garden soils, often places them in close proximity with humans. Most cases of disease caused by M. avium are pulmonary and the patient population includes individuals who are elderly, immune-compromised, or have preexisting lung damage due to an underlying respiratory disease (). Cases of M. avium disease have continued to rise, with cases increasing an estimated 5-10% annually in the United States (). M. avium pulmonary disease is both difficult to diagnose and treat. Once diagnosed, treatment with multiple antibiotics can last 18-24 months, with clinical guidelines indicating continuous treatment for 12 months after the infecting bacteria are no longer detected in patient sputum. Even with this extended treatment course, recurrence of infection is still common. M. avium is an intracellular pathogen with macrophages being the primary host cell. Therefore for the infection to be successful, the mycobacteria must adjust from living in its natural reservoir within a biofilm to invading and replicating in a macrophage. We know very little about how the mycobacteria makes this critical transition. We hypothesize that modifications of glycopeptidolipids, which are major cell surface molecules of M. avium, play a critical role in this transition and evidence showing their importance in biofilm formation and macrophage activation supports this argument. In Specific aim 1 we will test this hypothesis by isolating, from biofilm and macrophages, the different M. avium GPL species and characterize their ability to modulate macrophage function. We will also generate gene knockouts to produce GPL mutants and evaluate the M. avium mutants for biofilm formation and macrophage invasion/survival to define what GPL species are necessary for the observed phenotypes. In aim 2 we will perform a transcriptional analysis of M. avium grown in broth culture, biofilms and macrophages to define expression levels of the different genes involved in producing the various GPLs variants. The transcriptional analysis will have the added benefit of defining more globally, changes in gene expression which occur as the M. avium transitions from growth in biofilm to replication in macrophages.

项目概要像鸟分枝杆菌这样的非结核分枝杆菌是广泛存在的环境生物，发生在许多自然栖息地和人工栖息地中（）。鸟分枝杆菌的定殖能力家庭管道、热水浴缸和花园土壤，通常将它们放置在靠近人类。大多数由鸟分枝杆菌引起的疾病是肺部疾病，患者群体包括老年人、免疫力低下或已有肺损伤的人由于潜在的呼吸道疾病（）。鸟分枝杆菌病病例持续上升，美国的病例估计每年增加 5-10% ()。肺分枝杆菌疾病诊断和治疗都很困难。一旦确诊，应采取多种治疗抗生素可持续治疗 18-24 个月，临床指南表明持续治疗 12 个月几个月后，患者痰中不再检测到感染细菌。即使这样疗程延长，感染复发仍常见。鸟分枝杆菌是一种细胞内病原体，巨噬细胞是主要宿主细胞。所以为了成功感染，分枝杆菌必须适应其天然宿主的生活在生物膜内侵入巨噬细胞并在其中复制。我们对如何分枝杆菌实现了这一关键转变。我们假设修改糖肽脂是鸟分枝杆菌的主要细胞表面分子，在此过程中发挥着关键作用转变和证据表明它们在生物膜形成和巨噬细胞中的重要性激活支持这个论点。在具体目标 1 中，我们将通过隔离来检验这个假设：来自生物膜和巨噬细胞，不同的 M. avium GPL 物种并表征它们的能力调节巨噬细胞功能。我们还将生成基因敲除以产生 GPL 突变体并评估 M. avium 突变体的生物膜形成和巨噬细胞入侵/生存来定义哪些 GPL 物种对于观察到的表型是必需的。在目标 2 我们将对肉汤培养物、生物膜和中生长的鸟分枝杆菌进行转录分析巨噬细胞定义参与产生的不同基因的表达水平各种 GPL 变体。转录分析还有一个额外的好处，那就是定义更多在全球范围内，随着鸟分枝杆菌从生长转变为基因表达的变化，生物膜在巨噬细胞中复制。