Trypanosoma cruzi dormancy and its implications for therapeutic treatment

项目概要/摘要 微生物休眠被定义为代谢活动减少的状态，在细菌系统中被广泛认为是一种 对环境应激（包括抗生素治疗）的短暂抵抗的机制。我们最近报道过 克氏锥虫（恰加斯病的病原体）能够抵抗长期暴露于高细胞毒性化合物，因为 细胞内无鞭毛体亚群自发进入休眠状态的能力。这个新的 了解克氏锥虫生物学对当前可用药物的输送方式以及新药物的使用方式具有影响 可以鉴定能够逆转休眠的化合物。在此应用中，我们提出的实验将 如果不同的宿主组织，则定义不同寄生虫分离株之间克氏锥虫体内休眠的时间范围和限制 以及感染的慢性程度。将研究休眠的免疫学影响 这些寄生虫学和免疫学信息将被整合，以提高目前使用的治疗效果 可用药物。使用新型高内涵成像屏幕，我们将识别能够预防或逆转的小分子 休眠和/或驱动休眠和活跃复制的无鞭毛体向锥鞭毛体的阶段转换。 这些化合物将作为研究工具来研究与休眠相关的分子途径，并将 初步研究作为恰加斯病的新治疗实体。我们认为，观察休眠 T. cruzi 的发现及其在药物治疗失败中的明确作用是治疗设计和治疗的游戏规则改变者 克氏锥虫的药物发现。该提案中的工作为恰加斯病的治疗指明了前进的方向，使用新的方法 增强我们对决定治疗结果的复杂相互作用力的理解的工具，以及 整合这些信息以更好地使用现有药物并发现新药物。

Project Summary/Abstract Microbial dormancy, defined as a state of reduced metabolic activity, is well recognized in bacterial systems as a mechanism of transient resistance to environmental stresses, including antibiotic treatment. We have recently reported that Trypanosoma cruzi, the agent of Chagas disease, resists long-term exposure to highly cytotoxic compounds due to the ability of a subpopulation of intracelllular amastigotes to spontaneously assume a dormant state. This new understanding of T. cruzi biology has implications for how currently available drugs are delivered and how new compounds capable of reversing dormancy, may be identified. In this application, we propose experiments that will define the timeframe and limits of T. cruzi dormancy in vivo, among different parasite isolates, if different host tissues and with respect to the chronicity of the infections. The immunological implications of dormancy will be investigated and this parasitological and immunological information will be integrated to enhance treatment efficacy using currently available drugs. Using a novel high content imaging screen, we will identify small molecules that prevent or reverse dormancy and/or drive the stage conversion of both dormant and actively replicating amastigotes into trypomastigotes. These compounds will serve as research tools to investigate the molecular pathways involved in dormancy and will be preliminarily investigated as new therapeutic entities for Chagas disease. We believe that the observation of dormancy in T. cruzi and the demonstration of its clear role in drug treatment failure is a game changer for treatment design and drug discovery in T. cruzi. The work in this proposal charts a way forward for therapy for Chagas disease, using new tools to increase our understanding of the complex set of interacting forces that determine treatment outcomes, and integrating this information to better use current drugs and discover of new ones.