Retrotransposon assay for tick host bloodmeal identification

项目摘要/摘要。 莱姆病造成的公共卫生负担在美国东部继续扩大。 需要新的干预措施来降低风险，以补充众所周知的方法，如 杀螨剂或个人防护用品。有针对性的治疗方法，如口腔治疗 疫苗接种、杀螨剂喂养或基因改造目前正在开发中。 或者正在接受实地测试。这些较新的策略主要针对白足小鼠Permyscus 白纹伊蚊，被广泛认为是亚成虫(Ixodes Dammini Or)的主要宿主 肩周炎)，是莱姆病和其他各种人畜共患传染病的媒介。 事实上，这种老鼠已经被指控为美国东北部的主要物种。 莱姆病(莱姆病)和人类伯氏疏螺旋体的水库宿主 巴贝斯虫病(巴贝斯虫)和鹿虱病毒脑炎。然而，有证据表明P. 白纹伊蚊是亚成虫的主要宿主，在很大程度上是用间接描述性的 这是一种推断，由少数几个地点的有限观测数据组成。理想 判定水库宿主有罪的方法是确定所提供的血粉的来源 来感染媒介，但迄今为止描述的针对扁虱的检测方法一直很差 可复制的或不敏感的。我们对这个拟议项目的总体目标是提供一个 更好地了解其他寄主物种相对贡献的自然变异性的手段 关于莱姆病病原体的传播。这是评估成本和 老鼠靶向干预的好处。我们已经确定宿主反转录转座子可能 作为聚合酶链式反应检测的目标，并提供扁虱在其血液中摄入的血粉的特定签名 以前的阶段，现在寻求完善和验证这一分析模式。因此，我们寻求 建立并验证一种灵敏、特异、简单、重复性好的逆转录转座子检测方法 用于鉴定寻找寄主的若虫体内残留的寄主血粉；(2)使用 用于确定Permyscus血液指数(PBI)是否会在不同部位和不同部位内变化的化验方法 随时间推移的地点；以及(3)通过实施有针对性的干预措施来实验确认PBI 小鼠和化验宿主寻找若虫后，以确定是否有 是东道主的转变。尽管我们的直接目标是为MICE提供坚实的理论基础 针对莱姆病的有针对性的干预，该检测本身可以被调整为更好地 了解不同的其他壁虱传播的人畜共患病的传播模式。

Project Summary/Abstract. The public health burden due to Lyme disease continues to expand in the eastern United States. New interventions to reduce risk are needed to complement well-known methods such as acaricidal applications or personal protection. Reservoir targeted approaches such as oral vaccination, feed through acaricides or genetic modifications are currently under development or are being field tested. These newer strategies focus on the white footed mouse, Peromyscus leucopus, which is widely regarded as the main host for subadult deer ticks (Ixodes dammini or I. scapularis), the vector for Lyme disease and diverse other zoonotic infections in the northeastern U.S. Indeed, this mouse has been incriminated as the main northeastern U.S. reservoir host for the agent of Lyme disease (Borrelia burgdorferi) as well as for that of human babesiosis (Babesia microti) and deer tick virus encephalitis. However, the evidence that P. leucopus is the main host for subadult deer ticks is largely descriptive using indirect extrapolations and comprise limited observations from a small number of sites. The ideal means of incriminating a reservoir host is to determine the source of the bloodmeal that served to infect the vector but assays that have been described to date for ticks have been poorly reproducible or insensitive. Our overarching goal for this proposed project is to provide a means to better understand natural variability of the relative contribution of other host species on the transmission of the agent of Lyme disease. This is required to evaluate the costs and benefits of mouse targeted interventions. We have determined that host retrotransposons may be targeted by PCR assays and provide specific signatures of the bloodmeal taken by a tick in its previous stage, and now seek to refine and validate this mode of analysis. Accordingly, we seek to (1) develop and validate a sensitive, specific, simple and reproducible retrotransposon assay for identifying the remnants of host bloodmeals in host-seeking nymphal deer ticks; (2) use this assay to determine whether the Peromyscus blood index (PBI) may vary across sites and within sites over time; and (3) experimentally confirm the PBI by undertaking interventions targeted to mice and assaying host seeking nymphal deer ticks thereafter to determine whether there has been a shift in hosts. Although our immediate goal is to provide a solid rationale for mouse targeted interventions against Lyme disease, the assay itself could be adapted to better understand the mode of perpetuation of diverse other tick-borne zoonoses.