Role of Host Cell Factors in Herpes Simplex Virus (HSV) Keratitis

描述（由申请人提供）：我们将研究单纯疱疹1 （HSV-1）的两种细胞受体，疱疹病毒进入介质（HVEM）和连接素-1在角膜感染中的重要性，并通过小鼠敲除（KO）这些受体来建立潜伏期。细胞培养和小鼠体内HSV感染模型的研究表明，HVEM和nectin-1是介导进入的最有效途径，在HSV的发病机制中最重要。1型单纯疱疹病毒的再激活可导致口腔溃疡或更严重的疾病复发，包括脑炎和疱疹间质角膜炎（HSK）。HSK发病的确切机制尚不完全清楚，但已知的致病因素包括病毒复制和由此产生的免疫反应。我们计划研究角膜接种的结果，并检查哪些受体在易感组织（角膜上皮、角膜基质、TG神经元、TG非神经元细胞、免疫细胞等）中作为HSV-1的进入介质起作用。为了充分了解疾病的发病机制和开发治疗方法，了解HSV-1在眼部的靶组织是至关重要的。我们提出的研究将为进一步研究确定特定细胞类型（如免疫系统细胞）的感染是否在眼部HSV发病中起重要作用奠定基础。通过确定眼部感染中被HSV感染的精确细胞和病毒利用的受体，可以开发针对这些受体的新治疗方案。这种靶向治疗可能会减轻原发性感染和/或减少炎症免疫细胞，从而防止破坏性的后遗症，包括HSK、失明和脑炎。在Aim 1中，我们将通过确定HVEM和/或nectin-1是否为原发性HSV-1角膜感染所必需，来表征HVEM和nectin-1在原发性HSV-1角膜感染中的作用。我们还将评估输入病毒载量对带状虫状疾病发展的重要性，并确定眼部和TG中哪些细胞在原发性HSV-1感染期间被感染，以及这些细胞是否表达HVEM和/或nectin-1。在Aim 2中，我们将确定HVEM和/或nectin-1是否是三叉神经节HSV潜伏感染所必需的。

DESCRIPTION (provided by applicant): We will study the importance of two cellular receptors for herpes simplex 1 (HSV-1), herpes viral entry mediator (HVEM) and nectin-1, in the infection of the cornea and the establishment of latency by using mice knocked out (KO) for these receptors. Studies in cell culture and in vivo murine models of HSV infection indicate that HVEM and nectin-1 are the most efficient at mediating entry and most important in HSV pathogenesis. Reactivation of HSV-1 can lead to recurrent disease in the form of oral ulcers or more serious disease including encephalitis and herpes stromal keratitis (HSK). The precise mechanism of HSK pathogenesis is not fully understood, but factors known to contribute to disease include viral replication and the resulting immune response. We plan to study the outcome of corneal inoculation as well as examine which receptors function as HSV-1 entry mediators in susceptible tissues (corneal epithelium, corneal stroma, TG neurons, non-neuronal cells of the TG, immune cells, etc.). To fully understand disease pathogenesis and develop therapeutics, it is essential to understand the target tissues of HSV-1 in the eye. Our proposed studies will lay the foundation for further studies to determine whether infection of specific cell types, such as cells of the immune system, are important in HSV pathogenesis in the eye. By determining the precise cells infected by HSV in an ocular infection and the receptors utilized by the virus, novel treatment regimens can be developed that target those receptors. Such targeted therapies might attenuate primary infection and/or reduce inflammatory immune cells thereby preventing devastating sequelae including HSK, blindness, and encephalitis. In Aim 1, we will characterize the role of HVEM and nectin-1 in primary HSV-1 infection of the cornea by determining whether HVEM and/or nectin-1 are required for primary HSV-1 infection of the cornea. We will also evaluate the importance of input viral load on the development of zosteriform disease and determine which cells in the eye and TG are infected during primary HSV-1 infection and whether or not those cells are expressing HVEM and/or nectin-1. In Aim 2, we will determine whether HVEM and/or nectin-1 are necessary for HSV latent infection of the trigeminal ganglion. PUBLIC HEALTH RELEVANCE: Our specific aims are to identify the importance of the cellular receptors, HVEM and nectin-1, for HSV-1 infection of the eye. But more importantly how the use of these receptors contribute to herpes stromal keratitis (HSK). An understanding of the role for these receptors in HSK and how they contribute to disease will provide insight for the development of novel therapeutics for the treatment HSK which is the most frequent cause of corneal blindness in the US.