Discovery of new molecular phenotypes for anti-schistosomal drug screening

项目摘要：血吸虫寄生虫引起被忽视的局部疾病 血吸虫病。这种疾病感染了2亿人，但临床上只用一种药物治疗 广谱药物，吡喹酮(PZQ)。该病的广泛性和对PZQ耐药性的前景 强调替代疗法的必要性。事实上，据报道，PZQ治疗失败的现场和 抗性可以在实验室中进行选择，这表明抗性的长期遗传变异已经存在。 然而，由于我们对现有抗血吸虫药物的了解不足，药物发现工作受到了阻碍。 毒品起作用了。其中许多较老的化合物是40年前在活体动物筛选中发现的。这个 长期目标是确定治疗血吸虫病的可用药靶点/先导化合物。总体目标 这一应用的目的是解决血吸虫生物学中支撑其疗效的分子变化。 现有的抗血吸虫化合物，超越了蠕虫形态的表面描述，走向 可以分析新线索的量化端点。中心假设是驱虫药能唤起 比表面表型更有效的筛查终点的分子变化。其基本原理是 这个项目是，目前的血吸虫病药物发现工作往往集中在体外分析变化。 运动或形态，这不能很好地预测体内的疗效。一些抗血吸虫药物可以 引起蠕虫运动/形态的变化，但其他在体内有效，对运动没有影响 在体外，还有其他药物在体外阻碍运动，但在体内无效。更好地预测反- 需要寄生行动来开发更有成效的检测方法。我们将追求两个具体目标：(1)剖析 用一组分子分析方法研究10种不同化学成分的抗血吸虫药物的活性和(2) 识别具有不同作用机制的驱虫剂的转录签名。第一个目标是 通过系统评价解决这10种驱虫剂在作用机理上的异同 体内药物作用下蠕虫的细胞和分子变化。这些结果将作为以下目标的终点 未来筛查的定量分析的发展。第二个目的是比较转录 寄生虫对每种药物的反应，提供了对血吸虫生物学全球变化的公正读数 并允许根据推定的作用机制将药物入库。洞察比较性 抗血吸虫化合物的机制将使我们能够在发生以下情况时合理选择替代药物 PZQ治疗失败。这些信息也将为药物组合策略提供信息，以防止这种情况的出现 抗药性。这项应用中提出的研究具有重要意义，因为它将提供新的分析方法 对于未来的药物发现努力，比现有的更好地预测体内抗寄生虫的效果 蠕虫运动和形态的表面表型。这项研究之所以具有创新性，是因为它将 建立以机制为基础的检测方法，以确定抗击和预防耐药性的PZQ替代品。

PROJECT SUMMARY: Parasitic Schistosoma blood flukes cause the neglected topical disease schistosomiasis. This disease infects >200 million people but is clinically treated by monotherapy with just one broad spectrum drug, praziquantel (PZQ). The vast scope of the disease and the prospect of PZQ resistance highlight the need for alternative therapies. Indeed, PZQ treatment failure has been reported in the field and resistance can be selected in the lab, indicating that standing genetic variation for resistance already exists. However, drug discovery efforts are hampered by our poor understanding of how existing anti-schistosomal drugs work. Many of these older compounds were discovered >40 years ago using in vivo animal screens. The long-term goal is to identify druggable targets / lead compounds to treat schistosomiasis. The overall objective of this application is to resolve the molecular changes in schistosome biology that underpin the efficacy of existing anti-schistosomal compounds, moving beyond superficial descriptors of worm morphology towards quantitative endpoints that can be assayed for new leads. The central hypothesis is that anthelmintics evoke molecular changes that are more productive screening endpoints than superficial phenotypes. The rationale for this project is that current schistosomiasis drug discovery efforts often focus on in vitro assays for changes in movement or morphology, which are poor predictors of efficacy in vivo. Some anti-schistosomal drugs do cause changes in worm movement / morphology, but others are efficacious in vivo with no effect on movement in vitro, and still other drugs impair movement in vitro but are ineffective in vivo. Better predictors of anti- parasitic action are needed to develop more productive assays. We will pursue two specific aims: (1) Profiling the activity of 10 chemically diverse anti-schistosomal drugs using a panel of molecular assays and (2) Identifying transcriptional signatures of anthelmintics with distinct mechanisms of action. The first aim will resolve mechanistic similarities and differences between these 10 anthelmintics by systematically assessing cellular and molecular changes in worms exposed to drug in vivo. These outcomes will serve as endpoints for the development of quantitative assays for future screens. The second aim will compare the transcriptional responses of parasites to each drug, providing an unbiased readout of global changes to schistosome biology and allowing drugs to be binned according to putative mechanisms of action. Insight into the comparative mechanisms of anti-schistosomal compounds will allow us to rationally select alternative drugs in the event of PZQ treatment failure. This information will also inform drug-combination strategies to prevent the emergence of drug resistance. The research proposed in this application is significant because it will provide new assays for future drug discovery efforts that are better predictors of in vivo anti-parasitic efficacy than existing superficial phenotypes of worm movement and morphology. This research is innovative because it is will establish mechanism-based assays to identify PZQ-alternatives to combat and prevent drug resistance.