Breath Test for Pseudomonas aeruginosa in CF

CF 中铜绿假单胞菌呼气试验

基本信息

批准号：
7895581
负责人：
GRAHAM S TIMMINS
金额：
$ 22.5万
依托单位：
UNIVERSITY OF NEW MEXICO
依托单位国家：
美国
项目类别：
财政年份：
2009
资助国家：
美国
起止时间：
2009-07-17 至 2012-06-30
项目状态：
已结题

来源：
https://reporter.nih.gov/project-details/7895581
关键词：
Age Animal Model Antibiotic Therapy Anus Bacterial Antibiotic Resistance Bacterial Infections Breath Tests Breathing Characteristics Chemicals Chronic Clinical Clinical Trials Cyanides Cystic Fibrosis Data Detection Diagnostic Disease Management Dosage Forms Dose Drug Formulations Effectiveness Enzymes Exhalation Gene Expression Glycine Growth Helicobacter pylori Hereditary Disease High Prevalence In Vitro Infection Inflammatory Irrigation Isotopes Label Life Life Expectancy Lung Mass Spectrum Analysis Measures Metabolic Pathway Metabolism Microbial Biofilms Modality Modeling Monitor Mus Pathway interactions Patients Phase I Clinical Trials Phenotype Physiology Pseudomonas aeruginosa Regimen Research Personnel Respiratory physiology Sampling Specificity Sputum Stable Isotope Labeling Staging Stomach System Testing Time Translating Urea Urease Work denitrification drinking enzyme pathway improved mucoid novel novel diagnostics outcome forecast pre-clinical product development public health relevance pulmonary function decline ratiometric response stable isotope tool translational clinical trial

项目摘要

DESCRIPTION (provided by applicant): The progressive lung damage in cystic fibrosis (CF) arises from characteristic bacterial colonization with Pseudomonas aeruginosa being central After initial infection then colonization with wild-type strains, conversion of P. aeruginosa to the mucoid phenotype in the CF host occurs, increasing bacterial resistance to antibiotics and inflammatory lung damage, and causing declining pulmonary function and prognosis. There remains an unmet need for rapid, non-invasive diagnostic analysis of lung P. aeruginosa presence, burden and mucoid status. Such a diagnostic would enable real-time monitoring of infection, and also significantly improve CF management, that currently relies upon indirect measures such as lung function and culture of expectorated sputum (that is variable, samples only a part of the lung, not applicable to younger patients) or broncoalveolar lavage (that is invasive and unsuitable for repetitive use). We show that several isotopically labeled substrates can be uniquely converted by P. aeruginosa to volatile exhalable labeled gasses, in ways that depend upon bacterial phenotype. We therefore hypothesize that We can use P. aeruginosa-specific metabolism of stable isotopically-labeled compounds to exhaled gasses to determine lung infection, bacterial load, biofilm growth and mucoid status However, before we move to a translational clinical trial, we need to test our hypothesis, delineate the typical ratios of labeled volatiles in wild-type, biofilm and mucoid strains, and also demonstrate effectiveness in an animal model of CF lung infection with P. aeruginosa. We will therefore perform these aims: Specific Aim 1 Demonstrate and develop use of isotope ratio mass spectrometry to measure isotopically labeled gasses from denitrification, cyanide synthase and urease activities in P. aeruginosa in vitro. Specific Aim 2 Delineate the range of ratios of urease to cyanide synthase/denitrification products for non- mucoid and mucoid P. aeruginosa strains in vitro growing planktonically and in biofilms. Specific Aim 3 Demonstrate effectiveness of this diagnostic approach in mice with mucoid and non-mucoid P. aeruginosa lung infection. Successful completion of this preclinical stage would be followed by formulation work on an inhaled dosage form, and Phase 1 clinical trial. PUBLIC HEALTH RELEVANCE: Cystic fibrosis is a high-prevalence, life shortening genetic disease, with much of the lung damage coming from infection with P. aeruginosa. Yet, the clinical tools to monitor for P. aeruginosa presence, burden & phenotype, so that the infection can be actively and pro-actively managed are not suitable or available. We propose to test the potential of a novel breath test, that relies upon a unique panel of P. aeruginosa metabolic pathways to produce stable isotope labeled gasses from specific substrates. If successful, this work can be translated to provide a sensitive and rapid new diagnostic that could significantly improve management of this disease.

描述（由申请人提供）：囊性纤维化（CF）的进行性肺损害由特征性细菌定殖引起肺功能和预后。对肺假单胞菌的存在，负担和粘液状态的快速，非侵入性诊断分析仍未满足。这样的诊断将使感染实时监测，并显着改善CF管理，目前依赖于间接措施，例如肺功能和预期的支柱的培养（这是可变的，样品仅是肺的一部分，不适用于年轻患者）或broncoalcoalveolaveolaveolaveolavealveralveolaveal（这是侵入性且不适合重复使用）。我们表明，铜绿假单胞菌可以以依赖细菌表型的方式将几种同位素标记的底物唯一地转化为挥发性标记的气体。因此，我们假设我们可以使用稳定的同位素标记化合物的铜绿假单胞菌特异性代谢，以确定呼气的气体来确定肺部感染，细菌负荷，生物膜的生长和粘液状态，但是，在我们进行翻译的临床试验之前，我们需要测试我们的假设，典型的型号和典型的型号，并在实验室中进行典型效率和典型的volty率和典型的效率。粘液菌株，并且在铜绿假单胞菌的CF肺部感染动物模型中也表现出有效性。因此，我们将执行以下目的：特定目标1证明并发展同位素比质谱法以测量体外铜绿假单胞菌中的硝化，氰化物合酶和尿素酶活性的同位素标记的气体。具体目标2描绘了非粘液和粘液铜胞芽孢杆菌在体外生长的浮游生物和生物膜中的尿素酶与氰化物合酶/硝化产物的比率范围。具体目标3表明这种诊断方法在粘液和非粘液铜绿假单胞菌肺部感染中的小鼠中有效。成功完成此临床前阶段的完成将在吸入剂型和第1阶段临床试验上进行制定工作。公共卫生相关性：囊性纤维化是一种高尚的遗传疾病寿命缩短，大部分肺损害来自铜绿假单胞菌的感染。然而，监测铜绿假单胞菌存在，负担和表型的临床工具，以便可以主动和积极管理的感染不合适或可用。我们建议测试一种新型呼吸测试的潜力，该测试依赖于独特的铜绿假单胞菌代谢途径，以产生来自特定底物的稳定的同位素。如果成功，这项工作可以被翻译成可提供敏感且快速的新诊断，可以显着改善该疾病的管理。