Vector biology-Using a mosquito pathogen as a delivery system for anti-malarial a

媒介生物学-使用蚊子病原体作为抗疟疾药物的传递系统

• 批准号: 7660719
• 负责人: MARCELO JACOBS-LORENA
• 金额: $ 20.55万
• 依托单位: UNIV OF MARYLAND, COLLEGE PARK
• 依托单位国家: 美国
• 财政年份: 2009
• 资助国家: 美国
• 起止时间: 2009-03-01 至 2011-02-28
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/7660719
• 关键词: Adult; Anopheles gambiae; Antimalarials; Area; Attenuated; Binding; Biological Models; Biology; Culicidae; Dengue; Dose; Engineering; Filariasis; Goals; Human; Immune system; Immunization; Immunoglobulin Fragments; Insecta; Life; MCL1 gene; Malaria; Membrane Proteins; Mosquito-borne infectious disease; Outcome; Parasites; Peptides; Plasmodium; Plasmodium falciparum; Population; Prevalence; Probability; Proteins; Recombinants; Reproduction spores; Resistance; Salivary Glands; Scorpions; Screening procedure; Sporozoites; System; Testing; Time; Toxin; Transgenic Organisms; Vector-transmitted infectious disease; Viral Encephalitis; Virulence; Yellow Fever; base; circumsporozoite; design and construction; disease transmission; efficacy testing; fungus; human disease; hybrid gene; improved; killings; mortality; mutant; novel; pathogen; public health relevance; research study; response; tool; transmission process; vector

DESCRIPTION (provided by applicant): Around 46% of the World's population lives in areas where mosquito-borne diseases including malaria, filariasis, viral encephalitides, dengue and yellow fever are endemic. It was recently established that the insect pathogenic fungus Metarhizium anisopliae has the potential to control adult mosquitoes in an urban setting, but only if its potency is increased. Our goal is to produce one or more fungal products which can deplete anopheline and Plasmodium populations to the extent that marked reductions in malaria prevalence are achieved. We have already shown that M. anisopliae is a very effective delivery system for the insect-selective scorpion toxin AaIT, and that expressing AaIT produced a 9-fold reduction in effective spore doses against mosquitoes. This was very significant but kill times remain too slow for adequate protection. In this application, we propose experiments to compare several strategies for optimizing M. anisopliae's ability to curtail disease transmission. Mosquitoes infected with fungi showed a significant reduction in the number of sporozoites on salivary glands, but the mechanism responsible is unknown. We will carry out a detailed analysis of the interactions between Plasmodium, mosquitoes and M. anisopliae. This will include testing an attenuated strain of M. anisopliae that elicits a hyperimmune response to determine whether M. anisopliae can be used to immunize mosquitoes from Plasmodium. Further, we will compare mortality and sporozoite prevalence in mosquitoes infected with M. anisopliae strains expressing different combinations of insecticidal and anti-plasmodial proteins. It will be determined if these can be used synergistically to achieve effective reductions in transmission potential. Based on these results, we will also test the efficacy of using M. anisopliae to express synthetic multifunctional genes that are hybrids of different activities and that could, for example, target both the insect and the Plasmodium. The current proposal will: 1) explore the mosquito immune system; 2) develop tools and genetically engineered fungi that have the potential to greatly reduce malaria prevalence, and 3) develop M. anisopliae as a tractable model system that can be used to screen novel effectors. We envisage that after screening, the most potent effectors could be delivered against mosquitoes or Plasmodium by expression in M. anisopliae and/or in alternative pathogens, commensals or via transgenic mosquitoes. PUBLIC HEALTH RELEVANCE This project aims to design, construct and evaluate recombinant fungal pathogens that target adult mosquitoes and the malaria parasite. The most significant possible outcome of producing an optimized fungal pathogen will be a reduction of human disease as a result of interrupting transmission of the target parasite.

描述（由申请人提供）：世界上约有46％的人口居住在蚊子传播的疾病，包括疟疾，丝虫病，病毒性脑膜化，登革热和黄热病是地方性的。最近确定，昆虫致病的真菌元群有潜力在城市环境中控制成年蚊子，但前提是它的效力增加。我们的目标是生产一种或多种真菌产物，可以在疟疾患病率明显降低的范围内耗尽植物线和疟原虫种群。我们已经表明，昆虫分枝杆菌是一种非常有效的昆虫选择性蝎子毒素Aait的递送系统，并且表达AAIT的有效孢子剂量对蚊子的有效孢子降低了9倍。这是非常重要的，但是死亡时间仍然太慢，无法获得足够的保护。在此应用中，我们提出了实验，以比较多种优化Anisopliae减少疾病传播能力的策略。感染真菌的蚊子显示出唾液腺上孢子菌的数量显着减少，但造成的机制尚不清楚。我们将详细分析疟原虫，蚊子和小动脉菌之间的相互作用。这将包括测试一种衰减的弧菌菌株，该菌株会引起过度免疫反应，以确定是否可以使用大麻菌来使蚊子免疫疟原虫。此外，我们将比较感染了各种型虫菌株的蚊子中的死亡率和孢子岩患病率，这些蚊子表达了不同组合的杀虫剂和抗肿瘤蛋白。将确定是否可以协同使用它们以实现有效的传输潜力减少。基于这些结果，我们还将测试使用各种分枝杆菌表达与不同活性的杂种的合成多功能基因的功效，例如，这些基因可能同时针对昆虫和疟原虫。当前的提议将：1）探索蚊子免疫系统； 2）开发有可能大大降低疟疾患病率的工具和基因工程的真菌，3）开发出弧菌作为一种可拖动模型系统，可用于筛选新型效应子。我们设想，在筛选后，最有效的效应子可以通过在动脉粥样硬化和/或替代病原体，共生或通过转基因蚊子中表达在蚊子或疟原虫上传递。公共卫生相关性该项目旨在设计，建造和评估针对成年蚊子和疟疾寄生虫的重组真菌病原体。产生优化的真菌病原体的最重要的结果将是由于中断目标寄生虫的传播而减少人类疾病。