A Rabbit Model of Epstein-Barr Virus Infection

项目摘要 EB病毒（EBV）是一种疱疹病毒，其作为显著的人类病原体持续存在， 致癌潜力与其在免疫活性细胞内建立终身潜伏感染的能力有关。 主持人与绝大多数病毒不同，EB病毒相关疾病几乎完全是以下因素的结果： 潜伏感染而不是病毒复制造成的损害。例如，延迟会带来严重的问题， 在有效的抗EBV治疗剂的开发中，由于大多数这样的化合物被设计成 靶向病毒聚合酶和其它仅在病毒复制期间有活性的蛋白质;因此， 需要针对潜伏的EBV感染。此外，EBV的普遍存在性（约95%在成年期感染）和 它在人类免疫系统中建立的高度进化的平衡，使 有效的疫苗挑战。这两个挑战都可以通过生物学上准确和 易处理的EBV感染的动物模型，目前还不存在。令人惊讶的是，有关该事件的多份报告 近十年来，实验室兔作为EBV感染的模型提供了支持。在前期工作中，我们 已经证实了这些早期研究中最突出的观察结果，证实兔子确实是 感染，如病毒基因组的持续存在和与两者相关的EBV基因的表达所指示的。 病毒生命周期的潜伏和繁殖阶段。然而，需要进行几次关键的演示， 支持这一模型的真实性，从而在何种程度上可以应用于实验。在这 应用，我们提出了三个具体目标，以填补这些差距，通过互补的努力，由两个高级 一位是EB病毒领域的研究人员，另一位是在使用兔子作为模型方面具有相当专业知识的人。 病毒感染和免疫相关的研究。根据目标1，克莱尔博士将评估样本中的EBV感染。 上皮细胞组成部分的生命周期，包括使用器官型（筏）培养的原代上皮， 她开发并用于定义人类上皮细胞中EBV感染的模型。在目标2下，杰弗里博士 样品将利用他在EBV潜伏期领域的专业知识指导研究，以阐明是否建立 兔B细胞中持续感染的机制与人类中发生的过程相当。 B细胞室最后，尼尔克里斯滕森博士，利用他的专业知识与兔子模型将支持工作 在目标1和2下，以及在目标3中，将评估针对EBV感染的体液和细胞介导的免疫应答。 以及它们是否与对EBV感染的适应性免疫应答的关键方面相当 在自然宿主中总之，建议的工作将告知我们， 指示EBV在其人宿主中的生物学在兔中具有等同的功能：1）兔上皮细胞是否 支持EBV复制，这对病毒进入幼稚宿主至关重要; 2）是否持续存在 兔B细胞中的EBV是通过真实的潜伏感染建立的;以及3）是否存在可比较的适应性感染， 在兔中，免疫应答针对EBV感染而建立。

PROJECT SUMMARY Epstein-Barr virus (EBV) is a herpesvirus that persists as a notable human pathogen with significant oncogenic potential that is related to its ability to establish lifelong latent infection within an immunocompetent host. Unlike for the vast majority of viruses, EBV-associated diseases are almost exclusively a consequence of latent infection instead of damage caused by virus replication. Latency poses significant problems, for example, in the development of effective anti-EBV therapeutics, since the majority of such compounds are designed to target viral polymerases and other proteins active only during virus replication; novel approaches are therefore needed to target latent EBV infection. Moreover, the ubiquitous nature of EBV (~95% infected by adulthood) and the highly evolved equilibrium that it has established within the human immune system, make development of an effective vaccine challenging. Both of these challenges could be greatly aided by a biologically accurate and tractable animal model of EBV infection, which currently does not exist. Surprisingly, several reports over the last decade have provided support for the laboratory rabbit as a model of EBV infection. In preliminary work, we have confirmed the most salient observations from these earlier studies, confirming that rabbits are indeed infectable, as indicated by persistence of the viral genome and expression of EBV genes associated with both the latent and productive stages of the virus lifecycle. However, several critical demonstrations are required to support authenticity of this model, and thus the extent to which it could be applied experimentally. In this application, we propose three specific aims to fill these gaps through complementary efforts by two senior investigators in the EBV field, and a third who has considerable expertise in the use of the rabbit as a model for virus infection and immune-related studies. Under Aim 1, Dr. Clare Sample will assess EBV infection in the epithelial cell component of the lifecycle, including the use of organotypic (raft) cultures of primary epithelium, a model she has developed and used to define EBV infection in human epithelium. Under Aim 2, Dr. Jeffery Sample will employ his expertise in the field of EBV latency to direct studies to elucidate whether establishment of a persistent infection in rabbit B cells is mechanistically comparable to the process that occurs in the human B-cell compartment. Finally, Dr. Neil Christensen, employing his expertise with the rabbit model will support work under Aims 1 and 2, and in Aim 3 will assess the humoral and cell-mediated immune responses to EBV infection in the rabbit, and whether they are comparable to key aspects of the adaptive immune response to EBV infection in the natural host. In summary, the proposed work will inform us whether the three basic host components that dictate EBV biology in its human host are equivalently functional in the rabbit: 1) Whether rabbit epithelium supports EBV replication that is critical for passage of the virus onto a naïve host; 2) Whether persistence of EBV in rabbit B cells is established through an authentic latent infection; and 3) Whether a comparable adaptive immune response is mounted to EBV infection in the rabbit.