The Vampire Bat Virome: Evolutionary Implications in an Immunological Context

对野生动物的监测是检测具有人畜共患潜力的病毒的一项重要战略，这些病毒对人类和其他动物的健康构成威胁。最近在不同的蝙蝠物种中发现了几种病毒，其中许多病毒具有医学重要性，如SARS。然而，病毒监测研究仅在食虫蝙蝠或食果蝙蝠中进行，并且主要限于描述病毒的存在或不存在。关于普通吸血蝙蝠Desmodus rotundus的病毒流行病学和多样性知之甚少。吸血蝙蝠的取食行为涉及与其食物源的密切身体接触，这可以通过交换体液提供病原体传播的直接途径;因此，它代表了一种新颖且重要的研究模式。分子和系统发育分析表明宿主病毒共同进化和频繁的跨种传播事件。流行病学和进化过程之间的相互作用可以驱动病原体在宿主或人群中的时空发病率。尽管如此，导致宿主共适应的历史病原体相互作用可以通过有助于形成免疫受体的结构和遗传多样性的分子特征来检测。在哺乳动物物种中，病毒首先被先天免疫系统通过模式识别受体PRR（例如Toll样受体TLR）感知。TLR的遗传反应反映了一个物种的自然历史，但也可以定义免疫亚群。已检测到TLRs中在选择压力下进化的SNPs和位点与野生动物中的特定感染之间的相关性，表明TLRs的遗传变异在很大程度上受病原体相互作用的影响。因此，TLR是用于病毒宿主免疫动力学研究的极好模型。我们假设，吸血蝙蝠携带的非典型病毒株与人畜共患病的潜力。此外，在病毒分类群和病毒感应先天免疫TLR中检测到分子特征，揭示特定的病毒宿主相互作用共进化模式。因此，本研究的目的是揭示从墨西哥的自由放养吸血蝙蝠的样本人口的病毒组和吸血蝙蝠TLR参与病毒传感的特点。此外，我们将整合的数据在一个动态的背景下，通过使用分子进化的方法。拟议的项目旨在利用最先进的技术为新出现的人畜共患病和野生动物监测领域做出创新贡献。这项工作将使德国和我们的合作国墨西哥直接受益，因为它涉及双向科学交流，所获得的知识可能对拉丁美洲和欧洲的公共卫生和兽医卫生以及保护生物学研究具有重要意义。

Surveillance of wildlife is an important strategy for detecting viruses with zoonotic potential that represent a health risk both for humans and for other animals. Several viruses have been recently characterized in different bat species and many of these have medical importance, such as SARS. However, viral surveillance studies have been carried out only in insectivorous or fruit eating bats and have been mainly restricted on describing absence or presence of viruses. Little is known about the viral epidemiology and diversity among the common vampire bat, Desmodus rotundus. The vampire bat feeding behavior involves close body contact with its food source, which could provide a direct route of pathogen transmission via exchanged body fluids; therefore, it represents a novel and important study model. Molecular and phylogenetic analysis suggests host virus co evolution and frequent cross species transmission events. It is known that interaction between epidemiological and evolutionary processes may drive a pathogens spatiotemporal incidence within a host or population. Reversely, historical pathogen interactions that have led to co adaptation in a host may be detected by molecular signatures that have contributed in the shaping of the structural and genetic diversity of immune receptors. In mammalian species, viruses are first sensed by the innate immune system by pattern recognition receptors, PRRs, such as Toll like receptors, TLRs. TLRs phylogenies reflect the natural history of a species, but may also define immune sub populations. A correlation between SNPs and sites evolving under selective pressure in TLRs and specific infections in wildlife has been detected, showning that genetic variation at TLRs is largely influenced by pathogen interactions. Thus, TLRs are an excellent model for viral host phylodynamic studies. We hypothesize that vampire bats carry a repertoire of non canonical viral strains with zoonotic potential. Moreover, molecular signatures will be detected both in viral taxa and in the viral sensing innate immune TLRs, revealing specific viral host interaction co evolutionary patterns. Therefore, the aims of this study are to uncover the virome of a sample population of free ranging vampire bats from Mexico and to characterize the vampire bat TLRs involved in viral sensing. Further, we will integrate the data in a phylodynamic context, by using molecular evolutionary approaches. The proposed project intends to make innovating contributions to the fields of emerging zoonotic diseases and wildlife surveillance using state of the art technology. This work will be of direct benefit both to Germany and to our collaborating country Mexico, as it involves bidirectional scientific exchange and the knowledge gained could be of significance to public and veterinary health as well as conservation biology research both in Latin America and in Europe.