Toward Rapid, Non-Invasive, Highly Sensitive, Multiplex Detection of Respiratory Pathogens

 描述（由申请人提供）：目前肺炎的临床诊断方法通常需要数天或数周，并且总是需要患者的样本，通常是痰液。如果不能产生痰液，有时可以诱导痰液或进行肺灌洗，这两种方法都是侵入性的。根据世界卫生组织的数据，肺炎仍然是世界上5岁以下儿童死亡的主要原因之一，根据美国疾病控制和预防中心的数据，肺炎仍然是美国成年人的头号杀手之一。因此，迫切需要改进的诊断工具来检测肺部感染。达特茅斯的塞耶工程学院和佛蒙特州肺中心的研究小组已经开发了一种技术，该技术通过分析单一感染的呼出气中的感染特异性挥发物， 其可以在几分钟内生成诊断。在这项技术被用于人类之前，拟议的工作将完成剩余的必要实验。该假设是，呼出气体挥发物可用于诊断肺部感染，特别是用于区分不同的病原体，甚至在急性发热性疾病的合并感染期间。该假设将在两个特定目的中进行阐述：SA1：确定在小鼠模型中，呼吸挥发性分子是否可用于区分临床相关情况下的呼吸道细菌感染。这些实验将证明呼吸分子的子集反映了感染病因。该方法的有效性和特异性将使用混杂情况（如细菌合并感染（肺部和其他部位）以及抗生素治疗期间）来确定。该目的还将证明使用呼吸测定两种临床高度关注的微生物的抗生素敏感性（K.肺炎链球菌和S. aureus)具有良好的抗菌活性。SA2：确定呼吸挥发性分子在区分病毒和细菌感染中的效用。将确定细菌和病毒合并感染如何影响呼出气分析的诊断精度。使用甲型流感病毒、腺病毒和呼吸道合胞病毒，将证明免疫系统对病毒感染的应答导致可在呼吸中检测到并诊断感染病原学的分子的产生。所有细菌和病毒实验将使用已知的人类病原体，并将在成熟的动物模型中进行。本提案中的研究具有创新性，因为它利用了目前可用的最佳工具，在一系列临床相关的系统实验场景中测量呼吸分子。这些结果将代表着朝着呼吸道病原体检测的新概念系统迈出了稳健和实质性的一步。预计本研究的数据将支持即将进行的人体研究和临床用分析设备的开发。最终，该技术显示了从根本上改善患者诊断、监测和预后的前景。

 DESCRIPTION (provided by applicant): Current clinical diagnostic methods for pneumonia typically take days or weeks and always require a sample from the patient, typically sputum. If sputum cannot be produced, it can sometimes be induced or lung lavage can be taken, both invasive techniques. Pneumonia is still one of the world's leading causes of death for children under the age of 5 according to the WHO and one of the top killers for adults in the USA, according to the CDC. Hence, there is a critical need for improved diagnostic tools to detect lung infections. Research groups at Dartmouth's Thayer School of engineering and the Vermont Lung Center have developed a technique allowing for rapid, non-invasive diagnosis of airway infections by analyzing infection-specific volatiles in the exhaled breath for singular infections, which can generate a diagnosis within minutes. The proposed work will complete the remaining experiments necessary before this technology is taken to a human population. The hypothesis is that that exhaled breath volatiles can be used to diagnose infections of the lung, and specifically, to distinguish between different pathogens, even during co-infection, for acute febrile illnesses. The hypothesis will be addressed in two specific aims: SA1: To determine whether breath volatile molecules can be used to distinguish between respiratory bacterial infections during clinical-relevant scenarios in a murine model. These experiments will demonstrate that a subset of breath molecules reflect infection etiology. The validity and specificity of the approach will be determined using confounding scenarios such as bacterial co-infection (in the lung and elsewhere) as well as during antibiotic treatment. This aim will also demonstrate determination of antibiotic susceptibility using breath for two organisms of high clinical interest (K. pneumoniae and S. aureus). SA2: To establish the utility of breath volatile molecules to distinguish between viral and bacterial infections. It will be determined how bacterial and viral co-infection affects the diagnostic precision of the exhaled breath analysis. Using influenza A virus, adenovirus and respiratory syncytial virus, it will be demonstrated that the immune system response to viral infection leads to the generation of molecules that can be detected in the breath and are diagnostic of infection etiology. All bacterial and viral experiment will use known human pathogens and will take place in well-developed animal models. The research in this proposal is innovative because it utilizes the best tools currently available to measure breath molecules in a systematic series of clinically-relevant experimental scenarios. The outcomes will represent a robust and substantial step towards a novel conceptual system for respiratory pathogen detection. The data from this study is expected to support forthcoming studies in humans and the development of an analytical device for use in the clinic. Ultimately, the technology shows promise for radically improved patient diagnosis, monitoring, and prognosis.