Identification of aptamers for nanoparticle-based detection of Legionella pneumophila

嗜肺军团菌是军团病的病原体，军团病是人类的一种急性肺部感染。每年都会发生几次大规模的LD暴发，每一次都会影响数百人，并导致大约10%的受影响人口死亡。例如，2012年魁北克市暴发疫情导致183例病例和13人死亡。嗜肺性乳杆菌在水系统中生长，并通过吸入气雾剂传播给人类。为了防止军团病的爆发，必须充分管理供水系统，并在发现嗜肺杆菌时采取适当的行动。目前可用的检测方法很耗时，需要专业的技术技能。我们建议开发一种新的检测方法，该方法基于包裹有嗜肺杆菌特异性识别分子的纳米颗粒，称为适配子。这种纳米颗粒技术依赖于靶标存在时纳米颗粒涂层适配子的不同聚集模式。为此，我们将首先进行CELL-SELEX，在纳米颗粒技术所需的条件下鉴定与嗜肺乳杆菌特异结合的适配子，并确认候选适配子与嗜肺乳杆菌结合时与纳米粒结合。这一项目对于开发一种新的便携、易于使用和具有成本效益的水系统常规监测方法是必要的，这将有助于降低退伍军人病症的风险和负担。

Legionella pneumophila is the causative agent of Legionnaires' disease, an acute pulmonary infection in humans. Several large outbreaks of LD occur every year, each one affecting hundreds of people and resulting in the death of about 10% of the affected population. For example, the Quebec City outbreak in 2012 resulted in 183 cases and 13 deaths. L. pneumophila grows in water systems and is transmitted to human by inhalation of aerosols. To prevent outbreak of Legionnaires' disease it is imperative to manage water systems adequately and take appropriate action when L. pneumophila is detected in them. The current available detection methods are time consuming and require expert technical skills. We are proposing to develop a novel detection method based on nanoparticles coated with L. pneumophila-specific recognition molecules called aptamers. This nanoparticle technology relies on differential aggregation patterns of nanoparticle-coated aptamers when the target is present. To this end, we will first perform cell-SELEX to identify aptamers binding specifically to L. pneumophila under the conditions required for the nanoparticle technology and confirm the binding of the candidate aptamers to L. pneumophila when attached to nanoparticles. This project is necessary to develop a new portable, easy to use, and cost-effective method for routine monitoring of water systems that will help reduce the risk and burden of Legionnaires' disease.