The Molecular Pathogenesis of Varicella Zoster Virus Infection

描述（由申请人提供）：本项目旨在了解人类神经节中高度嗜神经性水痘带状疱疹病毒（VZV）的潜伏状态与病毒再激活引起的急慢性神经系统疾病的发展之间的关系。本项目包括一个行政核心、一个科研核心和3个科研项目。水痘带状疱疹病毒（VZV）的初次感染通常引起水痘（水痘），之后病毒潜伏在沿整个神经轴的人类神经节神经元中。随着年龄的增长，细胞介导的VZV免疫力下降导致病毒再激活，表现为带状疱疹（带状疱疹），其特征是局限于1-3个皮节的疼痛和皮疹。带状疱疹的发病率和严重程度在移植受者和癌症或艾滋病患者中也很高。带状疱疹经常并发慢性疼痛（带状疱疹后神经痛），以及瘫痪、失明和中风。目前，每年约有100万美国人患带状疱疹。奥卡VZV疫苗将带状疱疹的发病率降低了50%，但即使每个60岁以上的美国人都接种了疫苗，每年仍会发生50万例带状疱疹病例。本项目专门研究原发VZV感染、潜伏期和再激活的分子发病机制。项目1研究VZV感染神经元时，病毒和细胞蛋白对细胞凋亡的抑制作用，从而导致神经元存活和病毒潜伏期。

DESCRIPTION (provided by applicant): The goal of this program project is to understand the relationship between the latent state of the highly neurotropic varicella zoster virus (VZV) in human ganglia and the development of acute and chronic neurologic disease produced by virus reactivation. The program project contains an administrative core, a scientific core and 3 scientific projects. Primary infection by varicella zoster virus (VZV) usually causes varicella (chickenpox), after which virus becomes latent in human ganglionic neurons along the entire neuraxis. With aging, a declining cell-mediated immunity to VZV leads to virus reactivation, manifesting as herpes zoster (shingles) characterized by pain and rash restricted to 1-3 dermatomes. The incidence and severity of zoster is also high in transplant recipients and patients with cancer or AIDS. Zoster is frequently complicated by chronic pain (postherpetic neuralgia), as well as paralysis, blindness and stroke. Currently, ~1,000,000 Americans develop zoster annually. Oka VZV vaccine reduces the incidence of zoster by 50%, but even if every American over age 60 was vaccinated, >500,000 cases of zoster would still occur every year. This program project is focused exclusively on the molecular pathogenesis of primary VZV infection, latency and reactivation. Project 1 studies inhibition of apoptosis by both viral and cellular proteins during VZV infection of neurons that results in neuronal survival and viral latency. Project 2 studies molecular mechanisms of VZV latency and reactivation in ganglia, focusing on VZV IE63, the protein product of the most prevalent and abundant transcript identified in latently infected human ganglia, and whose translocation from the cytoplasm to the nucleus may result in altered IE63 function and induction of virus reactivation. Project 3 studies the immunobiology of varicella in an animal model, focusing on identification of host cell types and their role in transport and establishment of varicella infection in skin and ganglia during primary infection and cytokine expression and virus-specific T cells in varicella reactivation. A comprehensive knowledge of the physical state of latent and reactivated VZV and simian varicella virus (SVV) will provide the rational underpinning for strategies to prevent the cascade of events leading to human VZV reactivation, a cause of serious neurologic disease, particularly in the rapidly increasing elderly and immunocompromised populations. This proposal melds the skills and strategies of investigators with expertise in clinical neurology, virology, molecular and cell biology and clinical investigation.