Epstein Barr Virus Latency

描述（由申请人提供）：EB病毒是一种疱疹病毒，感染>90%的人群。它有两个显著的特点。首先，它能够在健康宿主中维持终身持续感染，其次，它与几种人类淋巴瘤和癌有关。这项建议将解决与这两项财产有关的核心问题。 持久性：EBV在记忆B细胞中建立持久的潜伏感染。关于它是如何做到这一点的，我们知道得很多，但对潜伏感染的细胞如何产生感染性病毒并传播到其他宿主的了解较少。我们的初步数据表明，病毒复制的信号是潜伏感染的细胞最终分化为浆细胞。我们将使用标准的分子生物学工具来确定浆细胞特异性转录因子在激活EBV裂解周期中的作用。由于浆细胞只有在完全分化时才能复制病毒，因此当它们迁移到骨髓时，它们可能会释放感染性病毒。这将导致早期B细胞祖细胞被感染。这些细胞还可以提供终身持续感染的部位。因此，本研究的第二个目的是检测骨髓作为病毒持续存在的第二个部位的作用。这将通过将骨髓分离成已知的B细胞亚群并通过我们开发的定量DNA和RT PCR技术检测病毒的存在来实现。 肿瘤：与EBV相关的最常见的肿瘤之一是鼻咽癌。 关于这种肿瘤的分子基础及其与EBV的关系仍然知之甚少。我们将使用Affytek芯片技术提供NPC的分子遗传学定义，以区分II型和III型（低分化和未分化的NPC）以及EBV编码的癌基因LMP 1阴性和阳性的肿瘤。我们的初步数据证明了这种方法的可行性。该分析将鉴定不同类型NPC的候选标记基因，并在体外和体内模型中测试它们的作用。具体来说，这种方法将用于识别LMP1激活的基因和信号通路。这将为阐明LMP1在鼻咽癌中的作用提供分子基础。

DESCRIPTION (provided by applicant): Epstein-Barr virus is a herpesvirus that infects >90% of the human population. It has two distinguishing characteristics. First it is able to maintain a life long persistent infection in healthy hosts and second it is associated with several human lymphomas and carcinomas. This proposal will address central issues related to these two properties. Persistence: EBV establishes a persistent latent infection in memory B cells. Much is known about how it does this but less is known about how the latently infected cell produces infectious virus to spread to other hosts. Our preliminary data indicate that the signal for viral replication is the terminal differentiation of the latently infected cell into a plasma cell. We will use standard molecular biological tools to identify the role of plasma cell specific transcription factors in activating the EBV lytic cycle. Since plasma cells replicate the virus only when they are fully differentiated it is likely that they release infectious virus when they migrate to the bone marrow. This would result in early B cell progenitors becoming infected. These cells could also provide a site of life time persistent infection. Therefore, the second aim of this study will be to test the role of the bone marrow as a second site of viral persistence. This will be achieved by fractionating the bone marrow into the known subsets of B cells and testing for the presence of the virus by quantitative DNA and RT PCR techniques that we have developed. Neoplasia: One of the commonest tumors associated with EBV is nasopharyngeal carcinoma. There remains little known about the molecular basis of this tumor and its association with EBV. We will use Affymetrix chip technology to provide a molecular genetic definition of NPC that distinguishes Type II and Type III (poorly and undifferentiated NPC) and tumors negative and positive for the EBV encoded oncogene LMP1. Our preliminary data demonstrates the feasibility of this approach. This analysis will identify candidate marker genes for the different types of NPC and test their roles in in vitro and in vivo models. Specifically this approach will be used to identify genes and signaling pathways activated by LMP1. This will provide a molecular basis for explaining the role of LMP1 in NPC.