Molecular mechanisms controlling secretion in filarial nematode parasites

项目概要 寄生线虫感染超过 15 亿人。控制这一与贫困相关的全球健康负担依赖于 几乎完全依靠少量驱虫药物的管理。驱虫药的前景 许多线虫寄生虫对这些药物的耐药性和次优性质需要新的方法 寄生虫治疗和控制。然而，开发新的抗寄生虫治疗方案的需要受到阻碍 由于我们对线虫生物过程的基础知识存在巨大差距，这些过程促进了线虫的建立和 维持感染。寄生线虫向宿主释放的排泄分泌 (ES) 产品 环境对于宿主免疫调节和成功寄生至关重要。尽管普遍欠缺 认为 ES 系统是释放促进寄生虫生长的分子（蛋白质和囊泡）的管道 生存，我们对医学上 ES 装置的基本结构和功能了解甚少 重要的寄生线虫。为了解决这一知识差距，该项目将确定分泌的监管者 马来丝虫是一种由蚊子传播的丝虫线虫，也是人类淋巴丝虫的病原体 雅病（LF）。最近对马来巴氏杆菌的研究，包括伊维菌素的作用方式，支持以下前提： ES 装置是一个利润丰厚且尚未开发的新治疗靶点来源。我们的总体假设 位于 B. malayi ES 系统的细胞表面受体直接或间接控制寄生虫的分泌 功能，并且它们可以有针对性地干扰 ES 衍生分子的释放。我们将追求 三个目标，由初步受体线索激发，并通过我们优化的创新方法实现 解析 B.malayi ES 系统的转录组状态并分析与寄生虫相关的受体 创建函数。我们的重点是 G 蛋白偶联受体 (GPCR)，这是多产的药物靶点 已知在线虫 ES 细胞和可能作用于 ES 系统的邻近细胞类型中表达。在 目标 1，我们将使用创新的空间转录组学方法来解析 B. malayi 的转录组 ES 区域跨越宿主内阶段并识别调节 ES 功能的候选 GPCR。在目标 2 中，我们将 使用反向遗传学和化学方法来评估 ES 定位的 GPCR 在调节中的作用 B.马来分泌功能。在目标 3 中，我们将使用全生物体模型线虫和哺乳动物单细胞 异源表达平台来定义 ES 定位 GPCR 的药理学并建立功能 GPCR 筛选分析。该项目的完成将产生关于丝虫的基本新知识 线虫 ES 系统，并为新型抗丝虫药物的发现提供新的先导靶点和经过验证的筛选。

Project Summary Parasitic nematodes infect over 1.5 billion humans. Control of this poverty-associated global health burden relies almost entirely on the administration of a small number of anthelmintic drugs. The prospects of anthelmintic resistance and the sub-optimal nature of these drugs in many nematode parasites demand new approaches to parasite treatment and control. However, the need to develop new antiparasitic treatment options is hampered by large gaps in our basic knowledge of the nematode biological processes that promote the establishment and maintenance of infection. Excretory-secretory (ES) products released by parasitic nematodes into their host environments are essential for host immune modulation and successful parasitism. Despite the general under- standing that the ES system is a conduit for the release of molecules (proteins and vesicles) that promote parasite survival, we have a poor understanding of the underlying structure and function of the ES apparatus in medically important parasitic nematodes. To address this gap in knowledge, this project will identify regulators of secretory function in Brugia malayi, a mosquito-transmitted filarial nematode and causative agent of human lymphatic filar- iasis (LF). Recent studies in B. malayi, including on the mode of action of ivermectin, support the premise that the ES apparatus is a lucrative and unexploited source of new therapeutic targets. Our overarching hypothesis is that cell-surface receptors localized to the B. malayi ES system directly or indirectly control parasite secretory function, and that they can be targeted to interfere with the release of ES-derived molecules. We will pursue three aims, motivated by preliminary receptor leads and made feasible by innovative methods we have optimized to resolve the transcriptomic state of the B.malayi ES system and to profile receptors implicated in parasite se- cretory function. We focus our efforts on G protein-coupled receptors (GPCRs), which are prolific drug targets and known to be expressed in nematode ES cells and adjacent cell types that may act on the ES system. In Aim 1, we will use innovative spatial transcriptomics approaches to resolve the transcriptome of the B. malayi ES region across intra-host stages and to identify candidate GPCRs that regulate ES function. In Aim 2, we will use reverse genetics and chemical approaches to assess the role of ES-localized GPCRs in the regulation of B. malayi secretory function. In Aim 3, we will use whole-organism model nematode and mammalian single-cell heterologous expression platforms to define the pharmacology of ES-localized GPCRs and to establish functional assays for GPCR screening. Completion of this project will produce fundamental new knowledge about the filarial nematode ES system and deliver new lead targets and validated screens for novel anti-filarial drug discovery.