Mechanism of artemisinin resistance in selected malaria parasite lines

描述(申请人提供)：具有多重抗药性的疟疾寄生虫恶性疟原虫是全球疟疾死灰复燃的主要因素。随着许多抗疟疾药物的失效，大多数疟疾流行国家都采用了以青蒿素为基础的联合疗法(ACT)来治疗恶性疟疾。虽然这是唯一一类临床上没有确证耐药性的抗疟疾药物，但世界许多地区关于青蒿素治疗失败的报道令人极为关切。青蒿素的确切作用模式和耐药机制知之甚少，这使得在青蒿素部署地区进行耐药性监测非常困难。在这里，我们建议使用实验室选择的青蒿素抗性寄生虫克隆来阐明青蒿素抗性的机制。利用最近开发的全基因组分析工具，我们建议1)使用高密度平铺阵列识别与耐药寄生虫相关的单核苷酸多态(SNPs)和拷贝数变异(CNV)；2)使用全基因组表达微阵列和定量蛋白质组学筛选可能导致青蒿素耐药性的序列多态。这些高通量方法将允许交叉检查和识别候选多态，这些多态可以在未来的研究中得到验证。 公共卫生相关性：为了应对疟疾控制中不断升级的抗药性问题，许多疟疾流行国家正在采用基于青蒿素的联合疗法。本研究旨在利用实验室筛选的青蒿素抗性品系更好地了解青蒿素的抗性机制。这项研究的结果可能使我们能够设计和实施对策，以密切监测和防止野外寄生虫种群对青蒿素的耐药性发展。

DESCRIPTION (provided by applicant): Multidrug-resistant malaria parasite Plasmodium falciparum is a major contributing factor to the global resurgence of malaria. With the failing of many antimalarial drugs, most malaria- endemic countries have adopted artemisinin-based combination therapy (ACT) to treat falciparum malaria. Although these are the only class of antimalarial drugs to which there is no confirmed clinical resistance, the reports of artemisinin treatment failures in many regions of the world are of great concern. The exact mode of action of artemisinins and the mechanism of resistance are poorly understood, making resistance surveillance in areas of artemisinin deployment very difficult. Here, we propose to use laboratory selected artemisinin-resistant parasite clones for elucidating the mechanism of artemisinin resistance. Using recently developed genome-wide analysis tools, we propose to 1) identify single nucleotide polymorphisms (SNPs) and copy number variations (CNVs) associated with the resistant parasites using high-density tiling arrays; and 2) filter out the sequence polymorphisms that might be responsible for the observed resistance to artemisinin using genome-wide expression microarray and quantitative proteomics. These high-throughput approaches will allow cross examination and identification of candidate polymorphisms that can be validated in future studies. PUBLIC HEALTH RELEVANCE: In response to the escalating problem of drug resistance in malaria control, artemisinin-based combinatory therapy (ACT) is being adopted by many malaria-endemic nations. This study aims at better understanding the resistance mechanism using laboratory selected artemisinin-resistant lines. The results from this study may allow us to design and implement countermeasures to closely monitor and prevent resistance development to artemisinins in field parasite populations.