Using Drosphila Macrophages to Study Innate Immunity

描述(申请人提供)：由分枝杆菌、沙门氏菌和李斯特菌等细胞内病原体引起的感染每年夺走全球数百万人的生命。这项提议将果蝇作为研究这些感染的模式生物。寄主和病原体的突变都将进行测试。果蝇以前曾被用来研究对革兰氏阳性和阴性细菌以及真菌的先天免疫反应。过去的工作只关注在细胞外空间自由生长的微生物。这项提案描述了将使用果蝇研究巨噬细胞内感染的实验。将测量引起果蝇巨噬细胞感染的几种细菌(海洋分枝杆菌、鼠伤寒沙门氏菌、单核细胞增生性李斯特菌)的生长特性，包括生长速度、致死率和位置。预计难以对抗细胞内病原体的果蝇突变体将接受细胞内感染防御能力的测试。将对鼠伤寒沙门氏菌突变株感染苍蝇的能力进行测试，以确定细菌基因在毒力中所起的作用。这些实验将为分析一组根据可能涉及细胞免疫反应的表型分离的果蝇突变体提供工具。

DESCRIPTION (provided by applicant): Infections caused by such intracellular pathogens as mycobacteria, Salmonella, and Listeria annually claim millions of lives worldwide. This proposal develops the fruit fly, Drosophila melanogaster as a model organism to study these infections. Mutations in both the host and pathogens will be tested. The fruit fly has been used previously to study innate immune responses to gram positive and negative bacteria as well as fungi. Past work focused only on microorganisms that grow freely in the extracellular space. This proposal describes experiments that will use Drosophila to study intracellular infections of macrophages. Growth characteristics including growth rate, lethality and location will be measured for several bacteria that cause infections of Drosophila macrophages (Mycobacterium marinum, Salmonella typhimurium, Listeria monocytogenes). Drosophila mutants expected to have difficulty fighting intracellular pathogens will be tested for their ability to defend against intracellular infections. Salmonella typhimurium mutants will be tested for their ability to infect the fly, to determine the role bacterial genes play in virulence. These experiments will provide tools to analyze a collection of Drosophila mutants isolated based upon a phenotype that is likely to involve the cellular immune response.