PLURIPOTENCY OF NOVEL TICK CYSTEINE PROTEASE INHIBITORS DURING HEMATOPHAGY

项目摘要 硬蜱在宿主身上吸血数天至数周。吸血是由蜱虫的 唾液反复注入宿主皮肤，与血液交替摄入。蜱唾液 含有多种生物活性分子的混合物， 机制，使蜱血液饲料的脊椎动物宿主数天，其中许多 是宿主免疫调节剂。了解蜱虫媒介之间的分子相互作用， 脊椎动物宿主和病原体是至关重要的发展战略，以打击蜱和蜱传 疾病该提案探讨了蜱吸血成功的基本机制，主要是 通过多个半胱氨酸调节脊椎动物宿主在蜱摄食部位（皮肤）的蛋白水解级联反应 胱抑素家族的蛋白酶抑制剂。我们假设三种新的斑点钝眼蜱 半胱氨酸蛋白酶抑制剂在吸血期间调节脊椎动物宿主的免疫应答。我们将测试 假设通过追求以下具体目标：1）完成详细的功能 三种新的重组斑点钝眼蜱唾液半胱氨酸蛋白酶抑制剂的表征 候选宿主免疫调节剂，2）研究三种A.海湾花 唾液胱抑素基因在蜱取食和病原体传播成功的条件敲除- 唐斯蜱的免疫应答（RNAi），以及，3）测试人工增强宿主体液应答的潜力 这三个A。通过在临床前动物模型中的疫苗研究， 最终目标是针对蜱半胱氨酸蛋白酶抑制剂的宿主抗体滴度的增强将阻断 它们在蜱-宿主界面的作用，并可能损害蜱的摄食和/或病原体传播 成功对于目标2，我们还将评估生物激发水凝胶作为非侵入性， 经表皮dsRNA递送装置，其可以提供商业上可扩展的方法， 在自然环境中对蜱虫进行这些治疗。这些目标将提供关键的 试剂，工具和数据，以解决在基本知识的作用， 蜱唾液中宿主免疫调节剂的冗余。

Project Summary Ixodid ticks blood feed for several days to weeks on their hosts. Hematophagy is assisted by tick’s saliva, which is repeatedly injected into the host skin, alternating with blood intake. Tick saliva contains a mixture of bioactive molecules that target a broad spectrum of host defense mechanisms to allow the tick to blood feed on the vertebrate host for several days, many of which are host immunomodulators. Understanding the molecular interactions between tick vectors, vertebrate hosts, and pathogens is critical in developing strategies to combat ticks and tick-borne diseases. This proposal explores a fundamental mechanism of tick hematophagy success, mainly regulating vertebrate host proteolytic cascades at sites of tick feeding (skin) by multiple cysteine protease inhibitors of the cystatin family. We hypothesize that three novel Amblyomma maculatum cystatins modulate the vertebrate host immune response during blood-feeding. We will test the hypothesis by pursuing the following specific aims: 1) To complete the detailed functional characterization of three novel recombinant Amblyomma maculatum salivary cystatins as candidate host immunomodulators, 2) To investigate the role of each of the three A. maculatum salivary cystatin genes in tick feeding and pathogen transmission success by conditional knock- downs in ticks (RNAi) and, 3) To test the potential of artificially boosting the host humoral response against these three A. maculatum cystatins by vaccine studies in a preclinical animal model, with an ultimate goal that the achieved boost in the host antibody titers against tick cystatins will block their action at the tick-host interface and may impair tick feeding and/or pathogen transmission success. For Aim 2, we will also evaluate the use of bio-inspired hydrogels as non-invasive, transcuticular dsRNA delivery devices that could provide a commercially scalable approach for the delivery of these therapies to ticks in their natural environment. These aims will provide critical reagents, tools, and data to address the crucial gap in the fundamental knowledge of the role of redundancy of host immunomodulators in tick saliva.