Dynamics of the Mosquito Heart: Hemolymph Flow and Associated Immune Cells

蚊子是世界性的害虫和疾病媒介。目前控制蚊子种群的方法主要依靠在蚊子血腔(体腔)或肠道中发挥杀虫功能的化学或生物制剂。在血腔中，杀虫剂通过血淋巴(血液)的自然流动传播到全身，并暴露在蚊子免疫和解毒因素下。此外，由蚊子传播的病原体通过血腔进行预定的迁移，在那里它们还必须压倒蚊子的免疫和解毒因素。在描述蚊子心脏的结构机制时，Hillyer和他的同事观察到，系统性细菌感染引发免疫细胞在心脏瓣膜周围区域(周围区)聚集，导致他们假设循环系统和免疫系统协同工作，以消除系统性感染。这项研究的目的是描述免疫细胞和蚊子心脏周围区之间的相互作用，以努力揭示蚊子循环系统和免疫系统之间生理相互作用的基本方面。目的1应用影像学方法对免疫细胞病灶的结构进行表征，确定免疫细胞病灶形成的动力学，并测试心脏收缩动力学是否因细菌感染而改变。目标2将使用分子和成像方法来发现调节蚊子心脏活动的激素。最后，目标3将测试操纵心脏收缩动力学是否改变周膜免疫细胞灶形成的动力学以及蚊子在全身感染中存活的能力。这些实验产生的数据可能有助于开发新的虫害和疾病控制策略。除了它的科学影响，这个项目还将导致对研究生、本科生和高中生进行生物学研究方面的培训。

Mosquitoes are cosmopolitan pests and disease vectors. Current methods for the control of mosquito populations rely primarily on chemical or biological agents that exert their insecticidal function in the mosquito hemocoel (body cavity) or in the gut. When in the hemocoel, insecticidal agents are spread throughout the body by the natural flow of hemolymph (blood) and are exposed to mosquito immune and detoxifying factors. In addition, pathogens transmitted by mosquitoes undergo an obligate migration through the hemocoel where they must also overpower mosquito immune and detoxifying factors. While characterizing the structural mechanics of the mosquito heart, Hillyer and colleagues observed that systemic bacterial infection elicited immune cells to aggregate in areas surrounding the valves of the heart (periostial regions), leading them to hypothesize that the circulatory and immune systems work in concert to eliminate systemic infections. The goal of this research is to characterize the interaction between immune cells and the periostial regions of the mosquito heart in an effort to uncover fundamental aspects of the physiological interaction between the mosquito circulatory and immune systems. Objective 1 will employ imaging methodologies to structurally characterize periostial immune cell foci, determine the kinetics of periostial immune cell foci formation, and test whether heart contraction dynamics change in response to bacterial infection. Objective 2 will employ molecular and imaging methodologies to uncover hormones that regulate mosquito heart activity. Finally, objective 3 will test whether manipulating heart contraction dynamics alters the kinetics of periostial immune cell foci formation and the ability of mosquitoes to survive a systemic infection. Data arising from these experiments could aid in the development of novel pest and disease control strategies. In addition to its scientific impact, this project will result in the training of graduate, undergraduate and high school students in biological research.