High Throughput Assay to Identify New Drugs Against Vivax Malaria Liver Stages

高通量测定法鉴定抗间日疟原虫肝期新药

• 批准号: 8479311
• 负责人: STEPHEN Lev HOFFMAN
• 金额: $ 30万
• 依托单位: SANARIA, INC.
• 依托单位国家: 美国
• 财政年份: 2012
• 资助国家: 美国
• 起止时间: 2012-06-04 至 2015-05-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/8479311
• 关键词: Antimalarials; Aotus primate; Biological Assay; Cell Line; Cells; Chemicals; Chemoprophylaxis; Coculture Techniques; Collaborations; Communities; Cultured Cells; Data; Development; Disease; Dose; Drug resistance; Equipment and supply inventories; Foundations; Genomics; Geographic Locations; Goals; Health; Hepatocyte; Human; In Vitro; International; Laboratories; Lead; Libraries; Liver; Malaria; Marketing; Methods; Monkeys; National Institute of Allergy and Infectious Disease; Parasites; Pattern; Pharmaceutical Preparations; Phase; Plasmodium falciparum; Plasmodium vivax; Preclinical Drug Evaluation; Publishing; Reading; Regimen; Relapse; Research; Shipping; Ships; Small Business Innovation Research Grant; Sporozoites; Staging; System; United States National Institutes of Health; Vivax Malaria; Work; base; cell type; economic impact; high throughput screening; in vivo; induced pluripotent stem cell; meetings; mortality; novel strategies; prevent; resistant strain; screening; success

DESCRIPTION (provided by applicant): Plasmodium vivax (Pv) is the 2nd most important human malaria parasite, causing more than 80 million cases annually, and significant severe disease and mortality that were previously unrecognized. Recent data indicate that the impact of Pv malaria on health and economies of the developing world has been dramatically underestimated. Pv is responsible for at least 30% of malaria in U.S. travelers. Efforts to prevent and control Pv malaria have had less than expected success due to emergence of drug resistant strains and repeated relapses from dormant liver stage called the hypnozoite. The international malaria research community has recently emphasized the critical need for increased research on Pv, if there is be successful elimination of this parasite. Modern approaches to development of new drugs against Pv, including hypnozoites are urgently needed. Sanaria is the only laboratory in the world, which has a functional assay in place for studying the effects of drugs against Pv liver stages and inventory of Pv sporozoites (PvSPZ) that can be used in such an assay. Many drug libraries are available for screening, but cannot be screened against Pv, because of lack of a medium or high throughput assay. The goal of this Phase I SBIR is to build on our current assay and inventory of PvSPZ to develop such an assay, initiate the screen for drugs against the liver stages of Pv, including hypnozoites. The long-term goal is to use the system to identify and develop new drugs that will eliminate all Pv liver stage parasites, including hypnozoites. Such drugs will be ideal for chemoprophylaxis of malaria in travelers and for mass-administration to eliminate Pv from defined geographic areas, therefore having both developed- and developing-world markets estimated to exceed $1 billion annually. Specifically we will: 1) Develop a reproducible, consistent, robust system for culturing liver stages of Pv and use it to screen for drugs against the liver stages of Pv. This will include assessing the use of HepG2 cells, primary human hepatocytes (PHH), and induced pluripotent stem cell-derived human hepatocytes (iPSDH) to establish an optimal cell- based screening system. 2) In collaboration with the Bhatia lab at MIT develop a reproducible, consistent, robust system of culturing Pv liver stages for at least 3-6 wks to identify and enrich for hypnozoites and screen drugs for activity against Pv hypnozoites. A micro-patterned co-culture system using PHH or iPSDH is being optimized to attain this goal. 3) In collaboration with the Inglese group at the NIH Chemical Genomics Center (NCGC) use the methods developed in Specific Aims 1 and 2 to screen a 2,500 compound library to identify target compounds with activity against liver stage parasites, including hypnozoites. 4) In collaboration with the Wellems group at NIAID/NIH produce, purify, and cryopreserve at least 2x108 fully infectious PvSPZ. In 2010, in collaboration with the Wellems group, we produced 108 fully infectious PvSPZ. These additional PvSPZ will be used in Phase II to conduct full scale screening of large compound libraries to identify and then characterize and develop lead compounds for development as anti-liver stage drugs. 1

描述（由申请人提供）：间日疟原虫（Pv）是第二种最重要的人类疟疾寄生虫，每年造成超过8000万例病例，以及以前未认识到的严重疾病和死亡率。最近的数据表明，Pv疟疾对发展中世界的健康和经济的影响被大大低估。在美国旅行者中，至少有30%的疟疾是由PV引起的。努力防止 和控制Pv疟疾的成功率低于预期，这是由于抗药性菌株的出现和被称为催眠虫的休眠肝脏阶段的反复复发。国际疟疾研究界最近强调，如果要成功消灭这种寄生虫，就迫切需要增加对Pv的研究。迫切需要现代方法来开发针对PV的新药，包括催眠虫。Sanaria是世界上唯一一家拥有功能性试验的实验室，该试验可用于研究药物对Pv肝脏阶段的影响以及可用于此类试验的Pv子孢子（PvSPZ）库存。许多药物文库可用于筛选，但由于缺乏中等或高通量测定，不能针对Pv进行筛选。该I期SBIR的目标是建立在我们目前的PvSPZ测定和库存的基础上，以开发这样的测定，开始筛选针对肝期Pv的药物，包括催眠虫。长期目标是使用该系统来识别和开发新的药物，以消除所有Pv肝脏阶段的寄生虫，包括催眠虫。这些药物将是理想的旅行者疟疾的化学预防和大规模管理，以消除从特定地理区域的PV，因此，发达国家和发展中国家的市场估计每年超过10亿美元。具体而言，我们将：1）开发用于培养Pv的肝脏阶段的可再现的、一致的、稳健的系统，并使用它来筛选针对Pv的肝脏阶段的药物。这将包括评估HepG 2细胞、原代人肝细胞（PHH）和诱导多能干细胞衍生的人肝细胞（iPSDH）的使用，以建立最佳的基于细胞的筛选系统。2)与麻省理工学院的Bhatia实验室合作，开发一种可重复的、一致的、稳定的培养Pv肝脏阶段的系统，至少3-6周，以鉴定和富集催眠虫， 筛选抗Pv催眠虫的药物。正在优化使用PHH或iPSDH的微图案化共培养系统以实现这一目标。3)与美国国立卫生研究院化学基因组学中心（NCGC）的英国小组合作，使用特定目标1和2中开发的方法筛选2，500种化合物库，以鉴定具有抗肝脏阶段寄生虫（包括催眠虫）活性的目标化合物。4)与NIAID/NIH的Wellems小组合作，生产、纯化和冷冻保存至少2x 108个完全感染性PvSPZ。2010年，我们与Wellems集团合作，生产了108个完全感染性PvSPZ。这些额外的PvSPZ将用于II期研究，对大型化合物库进行全面筛选，以鉴定、表征和开发先导化合物，用于开发抗肝脏阶段药物。1