Heritable immunization of the white-footed mouse reservoir of Lyme disease

项目摘要​​RFA-AI-19-037 莱姆病发病率的上升要求制定新的预防策略。现有方法 例如杀螨剂、减少鹿、美化环境和个人防护服，这些都是天生的 短期使用，必须定期重新涂抹、保养和磨损。用​将小鼠与扁虱对抗 该项目寻求开发一种持久的一次性干预措施，以破坏生态 莱姆病传播周期长达数十年​。莱姆的致病因子 伯氏伯氏杆菌病(​B.burgdorferi​)在扁虱和它们的小动物宿主之间来回传播， 作为人畜共患疾病的宿主。白足小白鼠​P.leucopus​ 被认为是最重要的水库，因为它既无处不在，又极其 通过扁虱有效地获取和传播病原体。我们的首要目标是 提议的项目是通过编码使白足小鼠遗传免疫来对抗莱姆病 保护性的​P​。白纹伊蚊​​抗体抗​B.burgdorferi​外表面蛋白A(OspA) 小鼠的生殖系。根据我们的计算，结合至少四种这样的抗体应该 阻止​B.burgdorferi​的进化逃逸，因为同时发生了太多OspA突变 将是需要的。至关重要的是，即使这些老鼠在某些领域没有现在那么重要 认为，免疫接种将减少被感染的扁虱的数量，这反过来将减少感染的人数 次级水库，这将感染较少的扁虱，强化了负反馈螺旋 预计将大大减轻当地莱姆病的负担。我们已经成功地 从OspA免疫的​P.leucopus​中分离到抗OspA抗体，推测为​P.leucopus 胚胎干细胞，并表明白蛋白基因似乎适合抗体分泌 取自肝脏。我们现在寻求(1)识别与至少四种不同的OspA结合的抗体 表位，(2)建立稳定的胚胎干细胞系并进行种系编辑，以及(3) 产生具有遗传抗性的小鼠，这些小鼠表达与 染色体易位，一种自然发生的高阈值基因驱动形式 这将使野生白纹伊蚊(​P.leucopus)的可逆和紧密定位工程成为可能 人口。我们的开放和社区引导的方法受到了明显的热情 南塔基特和玛莎葡萄园岛的居民表示，当地社区正在遭受 整个东北部和上中西部地区的壁虱传播疾病可能希望为他们的 几十年来，为了帮助预防莱姆病，我们拥有自己的野生老鼠种群。

Project Summary ​ ​ RFA-AI-19-037 The rising incidence of Lyme disease demands new strategies for prevention. Existing methods such as acaricides, deer reduction, landscaping, and personal protective clothing, are inherently short-term and must be regularly re-applied, maintained and worn. ​The Mice Against Ticks project seeks to develop a durable one-time intervention to disrupt the ecological cycle of Lyme disease transmission for many decades​. The causative agent of Lyme disease ​B. burgdorferi ​is passed back and forth between ticks and their small animal hosts, which serve as zoonotic reservoirs of disease. The white-footed mouse ​P. leucopus​ is widely considered to be the most important reservoir because it is both ubiquitous and extremely efficient at acquiring and transmitting pathogens via ticks. Our overarching goal for this proposed project is to heritably immunize white-footed mice against Lyme by encoding protective ​P​. ​leucopus​ antibodies targeting ​B. burgdorferi ​outer surface protein A (OspA) in the mouse germline. According to our calculations, combining at least four such antibodies should prevent evolutionary escape by ​B. burgdorferi ​because too many simultaneous OspA mutations would be needed. Crucially, even if these mice are less important in some areas than currently thought, immunization will reduce the number of infected ticks, which in turn will infect fewer secondary reservoirs, which will infect fewer ticks, reinforcing a negative feedback spiral anticipated to greatly reduce the local burden of Lyme disease. We have already successfully isolated anti-OspA antibodies from OspA-immunized ​P. leucopus​, derived putative ​P. leucopus embryonic stem cells, and shown that the albumin locus appears suitable for antibody secretion from the liver. We now seek to (1) identify antibodies that bind to at least four different OspA epitopes, (2) establish a stable embryonic stem cell line and perform germline editing, and (3) generate heritably resistant mice that express antibodies from a cisgenic cassette linked to a reciprocal chromosomal translocation, a naturally occurring form of high-threshold gene drive that would enable the reversible and tightly localized engineering of wild ​P. leucopus populations. Our open and community-guided approach has met with apparent enthusiasm by residents of Nantucket and Martha’s Vineyard, indicating that local communities suffering from tick-borne disease throughout the Northeast and Upper Midwest may wish to immunize their own wild mouse populations in order to help prevent Lyme disease for many decades.