Development and function of humoral immunity in the Jamaican fruit bat, Artibeus jamaicensis

项目摘要 蝙蝠身上携带着许多病毒，这些病毒看起来并不致病，但却能在人类和其他非蝙蝠动物身上引起致命的感染。 包括狂犬病、马尔堡热病毒和SARS相关冠状病毒。更好地了解 蝙蝠的免疫系统--它如何对病毒作出反应，它与人类免疫系统有何不同--可能导致 治疗甚至避免人类感染的改进方法。免疫反应由两个组成 主要分支：非特异性先天反应和病原体特异性适应性反应。虽然 许多研究已经调查了蝙蝠的先天免疫，但对它们的适应性免疫知之甚少。 系统拟议研究的长期目标是加强对适应性免疫的理解， 蝙蝠获得性免疫的一个关键特征是体液免疫;这种免疫应答由抗体介导， 也称为免疫球蛋白。高度多样性的免疫球蛋白库是通过 抗体的基因重组、DNA插入和缺失以及体细胞突变的组合 顺序虽然在蝙蝠的几项血清学研究中检测到了免疫球蛋白，但 蝙蝠免疫球蛋白库的多样性，蝙蝠依赖基因重排与体细胞的程度 突变产生这些库，免疫球蛋白的突变如何与免疫球蛋白的中和相关。 病原体或感染后产生的B细胞亚群仍然未知。拟定的研究将 使用狂犬病毒疫苗接种，然后在牙买加果蝠狂犬病毒感染，以产生最 全面了解蝙蝠B细胞介导的适应性免疫。牙买加果蝠 在中美洲和南美洲很常见，狂犬病仍然是一个严重的威胁， 狂犬病病毒。这项研究将使用长读测序来表征提供基因表达的种系基因。 免疫球蛋白库的起始多样性。下一代基因组技术将用于跟踪 重排免疫球蛋白库的开发，监测特异性B细胞克隆的扩增，以及 在疫苗接种和用以下物质攻击期间，量化抗原暴露的抗体中的体细胞突变程度： 狂犬病单细胞转录组学将用于表征免疫应答中产生的B细胞亚群。 挑战，结合试验和狂犬病中和试验将有助于了解抗体如何 成熟与功能相关。蝙蝠对疫苗接种和感染的免疫应答比较 将用于研究受控和自然环境下的免疫力。这项研究将提供重要 蝙蝠的适应性免疫系统的信息，目前缺乏。这些数据将提供洞察力， 蝙蝠和人类对共同病原体的免疫反应差异，可用于 开发新的狂犬病预防或干预方法。产生的框架和免疫学数据 该项目还将允许对任何感染的B细胞介导的免疫力进行特定研究。

Project Summary Bats host many viruses, seemingly without disease, that cause lethal infections in humans and other non-bat species, including rabies, Marburg fever virus and SARS-related coronaviruses. A greater understanding of the bat immune system – how it responds to viruses, how it differs from the human immune system – could lead to improved approaches for treating or even avoiding infection in humans. The immune response consists of two major branches: the nonspecific innate response and the pathogen-specific adaptive response. Although numerous studies have investigated innate immunity in bats, very little is known about their adaptive immune system. The long-term objective of the proposed research is to enhance understanding of adaptive immunity in bats. A key feature of adaptive immunity is humoral immunity; this immune response is mediated by antibodies, also known as immunoglobulins. The hyper-diverse immunoglobulin repertoire is generated through a combination of gene recombination, DNA insertions and deletions, and somatic mutation of the antibody sequence. While immunoglobulins have been detected in several serological studies of bats, the true extent of the diversity of bat immunoglobulin repertoires, the degree to which bats rely on gene rearrangement vs. somatic mutation to generate these repertoires, how mutation of the immunoglobulins correlates with neutralization of pathogens, or the B cell subsets that arise in response to infection remain unknown. The proposed study will use rabies virus vaccination followed by rabies virus infection in Jamaican fruit bats to generate the most comprehensive understanding of B cell-mediated adaptive immunity in bats to date. Jamaican fruit bats are common across Central and South America, where rabies remains a serious threat, and are naturally infected by rabies virus. This research will use long-read sequencing to characterize the germline genes that provide the starting diversity for the immunoglobulin repertoire. Next generation genomic techniques will be used to track the development of rearranged immunoglobulin repertoires, monitor expansion of specific B cell clones, and quantify the degree of somatic mutation in antigen-exposed antibodies across vaccination and challenge with rabies. Single-cell transcriptomics will be used to characterize the B cell subsets that arise in response to immune challenges, and binding assays and rabies neutralization tests will facilitate an understanding of how antibody maturation correlates with function. Comparison of the immune responses of bats to vaccination and infection will be used to investigate immunity in controlled and natural contexts. This research will provide important information on the adaptive immune system of bats that is currently lacking. These data will provide insight into the differences in immune responses between bats and humans to a shared pathogen and can be used to develop new rabies prevention or intervention approaches. The framework and immunological data generated by this project will also allow for specific investigations of B-cell mediated immunity to any infection.