Ecological immunology of a flea vector (Ctenocephalides felis)

项目总结/摘要 跳蚤是细菌病原体的专性载体，这些细菌病原体在人类中引起严重疾病，包括鼠斑疹伤寒 和黑死病为了抵抗或限制感染，跳蚤拥有先天免疫系统， 抵抗微生物的入侵和定居然而，在它们的自然栖息地，跳蚤种群是由 个体不仅遗传背景不同，而且性别、年龄、饮食、 感染史、肠道微生物群和暴露于环境应激因素。这些非遗传因素 显示对其他疾病媒介的感染结果有重要影响;然而，没有研究表明， 迄今为止，已经讨论了这些生态参数对跳蚤免疫反应的影响。拟议 研究旨在填补跳蚤生态免疫学的知识空白，主要目标是 确定影响成虫抗菌反应的内在因素，并确定幼虫的作用 生态学对成年后感染的影响。具体来说，我们建议比较免疫防御的强度， 基于性别、年龄和感染史的成年猫蚤（猫栉首蚤）机制（具体目标1）， 以及幼虫暴露于食物量、幼虫密度和杀虫剂后（具体目标2）。这个项目 将提供有价值的洞察跳蚤免疫力的变化在自然条件下，这可以直接影响 病原体传播动力学和改变病媒种群内的疾病流行结果。产生的数据 这一项目的成果可以帮助开发新的策略来控制跳蚤传播的病原体的传播 对人类

PROJECT SUMMARY/ABSTRACT Fleas are obligate vectors of bacterial pathogens that cause severe diseases in humans, including murine typhus and bubonic plague. To resist or limit infection, fleas possess an innate immune system that provides defense against microbial invasion and colonization. However, in their natural habitats, flea populations are made up of individuals that differ not only their genetic background, but also in regard to factors such as sex, age, diet, infection history, gut microbiota, and exposure to environmental stressors. These non-genetic factors have been shown to have important consequences on the outcome of infection in other disease vectors; yet, no studies to date have addressed the impact of these ecological parameters on flea immune responses. The proposed research aims to fill these knowledge gaps in flea ecological immunology, with the primary goals being to determine the intrinsic factors that affect the antibacterial response in adults, and to determine the effect of larval ecology on subsequent infections as adults. Specifically, we propose to compare the strength of immune defense mechanisms in adult cat fleas (Ctenocephalides felis) based on sex, age, and infection history (Specific Aim 1), as well as following larval exposure to food quantity, larval density, and insecticides (Specific Aim 2). This project will provide valuable insight into the variability of flea immunity under natural conditions, which can directly affect pathogen transmission dynamics and alter disease prevalence outcomes within a vector population. Data arising from this project could aid in the development of novel strategies to control the spread of flea-borne pathogens to humans.