Genetic Analysis of Interactions Between Oral Innate Immunity and a Herpesvirus

描述(由申请者提供)：口腔代表着一个独特的身体部位，它与外部世界接触，因此不断地遇到各种各样的微生物。疱疹病毒是人类口腔中重要的常驻病原体。然而，关于宿主在初次感染、口腔潜伏和重新激活期间如何感知和反应疱疹病毒，特别是关于先天性免疫系统，人们知之甚少。病毒和其具有免疫活性的宿主共存需要在病毒复制和宿主清除之间取得微妙的平衡。阐明先天免疫系统和疱疹病毒之间的相互作用将为如何实现和调节这种平衡提供洞察力。小鼠伽马疱疹病毒68(MHV-68)感染的小鼠模型为探索口腔中病毒与宿主的相互作用提供了一个很好的系统，原因有几个。首先，口服后，MHV-68病毒在口鼻腔和唾液腺中复制。其次，一种顺从的遗传系统可以用来诱变MHV-68病毒基因组。第三，MHV-68可以感染多种实验室菌株的小鼠，这使得可以在体内研究细胞基因在病毒感染过程中的作用。 我们的发现驱动方法的长期目标是通过使用敲除小鼠和一组MHV-68突变病毒来确定病毒和细胞蛋白在病毒相关发病机制中的作用。MHV-68基因组通过插入应答子而随机中断。有32个病毒开放阅读框不是在成纤维细胞中复制所必需的，它们可能参与调节病毒与宿主的相互作用。这一探索性的R21应用的目的是利用小鼠口服MHV-68感染的模型来确定TLR及其信号通路在体内的传感和防御作用。此外，我们将系统地筛选能够抑制细胞中抗病毒反应激活的病毒基因，这是了解病毒与宿主相互作用的关键步骤。

DESCRIPTION (provided by applicant): The oral cavity represents a unique body part that is in contact with the external world and therefore constantly encounters a vast diverse of microbes. Herpesviruses are significant resident oral pathogens in humans. However, little is known about how the host senses and responds to herpesviruses during primary infection, latency and reactivation in the oral cavity, especially in regards to the innate immune system. Coexistence of a virus and its immunocompetent host entails a delicate balance between viral replication and host clearance. Elucidating the interactions between the innate immune system and herpesviruses will provide insights to how the balance is accomplished and regulated. A mouse model of murine gammaherpesvirus-68 (MHV-68) infection provides an excellent system to explore virus-host interactions in the oral cavity for several reasons. First, following oral administration, MHV-68 replicates in the oronasal cavity and the salivary gland. Second, an amenable genetic system is available to mutagenize the MHV-68 viral genome. Third, MHV-68 infects a variety of laboratory strains of mice, which allows the role of cellular genes during viral infection to be studied in vivo. The long-term goal of our discovery driven approach is to determine the role of viral and cellular proteins in virus-associated pathogenesis by employing knock-out mice and a collection of MHV-68 mutant viruses. The MHV-68 genome is randomly disrupted by an insertion of a transponson. There are 32 viral ORFs that are not required for replication in fibroblast cells and potentially involved in modulating virus-host interactions. The object of this exploratory R21 application is to define the in vivo sensing and defending role of TLR and its signaling pathway using a mouse model of oral MHV-68 infection. Furthermore, we will systematically screen viral genes that are capable of inhibiting the activation of anti-viral responses in cells, an essential step for understanding virus-host interactions.