Varicella Zoster Virus Latency in Human Ganglia

水痘带状疱疹病毒（VZV）是一种普遍存在的人类病原体。原发性感染会导致儿童水痘，导致脑神经、背根和自主神经节出现潜伏期。VZV再激活，常见于老年人和免疫功能低下的人群，导致严重的神经系统疾病。带状疱疹和带状疱疹后神经痛占主导地位，但许多人发展为肌无力，节段性运动无力，颅神经麻痹，以及严重的，通常是神经麻痹。 致命的脑血管病变我们还发现，VZV再激活可在没有皮疹的情况下产生慢性剧烈疼痛。虽然控制VZV潜伏期的机制尚不清楚，但它很可能依赖于病毒基因转录，从而为我们的假设提供了理论基础，即VZV基因在潜伏期的人类神经节中的表达起到维持潜伏感染的作用。VZV潜伏期基因表达的鉴定是了解潜伏感染的关键。在高通量阵列技术出现之前，这种分析是不可行的，并且已经分析了<20%的VZV基因组的潜伏病毒转录物。此外，仅仅鉴定潜伏转录的VZV基因是不够的。由于VZV潜伏期的控制可能涉及病毒蛋白，表征潜伏表达的病毒蛋白对于理解病毒基因调控也是至关重要的。因此，我们的长期目标是详细描述VZV基因表达，包括功能分析， 潜伏感染的人类神经节我们的具体目标是：（1）通过转录阵列分析鉴定潜伏转录的VZV基因，通过测序确认转录物的真实性，并通过基于荧光的定量PCR确定病毒转录物的丰度。（2）构建高亲和性表位标记的重组抗体，通过原位免疫组化共定位人神经节切片中潜伏表达的VZV蛋白;和（3）使用双杂交系统启动蛋白质功能分析以鉴定和绘制蛋白质-蛋白质相互作用。我们将开始与VZV IE 63，最普遍和丰富的病毒转录检测到的日期在潜伏期。深入了解潜伏感染的人类神经节中VZV基因的表达和功能，将导致潜伏病毒基因调控的可测试模型（在发展中的猿猴水痘病毒模型中），以及旨在降低与这种高度嗜神经的人类病原体的再激活相关的发病率和死亡率的治疗方法。

Varicella zoster virus (VZV) is an ubiquitous human pathogen. Primary infection causes childhood chickenpox, leading to latency in cranial nerve, dorsal root and autonomic ganglia. VZV reactivation, frequent in the elderly and immunocompromised population, results in significant neurological disease. Zoster and postherpetic neuralgia predominate, but many humans develop myelitis, segmental motor weakness, cranial nerve palsies, and a severe, often fatal vasculopathy in the brain. We have also shown that VZV reactivation can produce chronic intense pain in the absence of rash. Although the mechanism controlling VZV latency is not understood, it is likely to depend upon virus gene transcription, thus providing the rationale for our hypothesis that VZV gene expression in human ganglia during latency functions to maintain latent infection. Identification of the VZV genes expressed during latency is critical to understanding latent infection. Until the advent of high throughput array-based technology, such analyses were not feasible, and <20% of the VZV genome has been analyzed for latent virus transcripts. Further, merely identifying the latently transcribed VZV genes is insufficient. Since control of VZV latency is likely to involve virus proteins, characterization of latently expressed viral proteins is also critical to understanding virus gene regulation. Thus, our long-term goal is the detailed characterization, including functional analysis, of VZV genes expressed in latently infected human ganglia. Our specific aims will: (1) identify latently transcribed VZV genes by transcriptional array analysis, confirm the authenticity of the transcripts by sequencing, and determine the abundance of the virus transcripts by fluorescence-based quantitative (real-time) RT-PCR; (2) construct high affinity epitope-tagged recombinant antibodies to colocalize latently expressed VZV proteins by in situ immunohistochemistry in sections of human ganglia; and (3) initiate protein function analysis using 2-hybrid systems to identify and map protein-protein interactions. We will begin with VZV IE63, the most prevalent and abundant virus transcript detected to date during latency. An in-depth understanding of VZV gene expression and function in latently infected human ganglia will lead to testable models of latent virus gene regulation (in the developing simian varicella virus model) and to therapies designed to reduce morbidity and mortality associated with reactivation of this highly neurotropic human pathogen.