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）：世界上大约 46% 的人口生活在疟疾、丝虫病、病毒性脑炎、登革热和黄热病等蚊媒疾病流行的地区。最近发现，昆虫病原真菌金龟子绿僵菌有潜力控制城市环境中的成蚊，但前提是其效力必须增强。我们的目标是生产一种或多种真菌产品，这些产品可以消耗按蚊和疟原虫种群，从而显着降低疟疾患病率。我们已经证明，M. anisopliae 是昆虫选择性蝎子毒素 AaIT 的非常有效的传递系统，并且表达 AaIT 可使针对蚊子的有效孢子剂量减少 9 倍。这非常重要，但杀死时间仍然太慢，无法提供足够的保护。在此应用中，我们提出了实验来比较几种优化金龟子分枝杆菌减少疾病传播能力的策略。感染真菌的蚊子唾液腺上的子孢子数量显着减少，但其机制尚不清楚。我们将对疟原虫、蚊子和马铃薯疟原虫之间的相互作用进行详细分析。这将包括测试能引发超免疫反应的金龟子分枝杆菌减毒株，以确定金龟子分枝杆菌是否可用于对蚊子进行疟原虫免疫。此外，我们将比较感染表达不同杀虫和抗疟原虫蛋白组合的 M. anisopliae 菌株的蚊子的死亡率和子孢子流行率。将确定这些是否可以协同使用以实现有效减少传输潜力。基于这些结果，我们还将测试使用 M. anisopliae 表达合成多功能基因的功效，这些基因是不同活性的杂交体，例如可以同时针对昆虫和疟原虫。目前的提案将：1）探索蚊子的免疫系统； 2) 开发有潜力大大降低疟疾流行的工具和基因工程真菌，以及 3) 开发 M. anisopliae 作为可用于筛选新型效应器的易于处理的模型系统。我们设想，筛选后，最有效的效应物可以通过在M. anisopliae和/或在替代病原体、共生体中或通过转基因蚊子中表达来传递以对抗蚊子或疟原虫。公共卫生相关性 该项目旨在设计、构建和评估针对成年蚊子和疟疾寄生虫的重组真菌病原体。生产优化的真菌病原体最重要的可能结果是通过中断目标寄生虫的传播来减少人类疾病。