Immune Induction to Genital Herpes Simplex Virus 2

描述（由申请人提供）：单纯疱疹病毒-2 （HSV-2）是最常见的性传播感染（STIs）之一，在美国的患病率为4500万。HSV-2通过暴露在生殖器粘膜表面传播，导致骶神经节潜伏，导致无法治愈的疾病。虽然与2型单纯疱疹病毒相关的症状可以用抗病毒药物暂时治疗，但目前还没有预防这种疾病的疫苗。为了研制出有效的2型单纯疱疹病毒疫苗，有必要清楚地了解相关粘膜部位产生免疫反应的机制。目前，对女性生殖器粘膜内免疫应答的启动过程了解甚少。因此，本研究的目的是了解HSV-2感染后女性生殖道中抗原呈递树突状细胞（dc）介导的局部保护性免疫的诱导机制。在本申请中，我们以第一个资助期的发现为基础，提出了三个不同但相互关联的目标。在第一篇论文中，基于我们的初步数据表明，在HSV-2感染后，toll样受体（TLR）和CD4 T都需要帮助产生CTL反应，我们建议剖析这两种信号使dc启动CTL反应对抗生殖器疱疹感染的机制。接下来，基于我们的证明，tlr介导的阴道角化细胞对HSV-2感染的识别对于粘膜下dc （smdc）在体内诱导强大的Th1免疫是必要的，在第二篇论文中，我们建议鉴定导致这种作用的角化细胞产生的因子，并研究它们在体内抗HSV-2免疫中的相关性。在最后的目的中，我们建议通过产生SMDC可诱导敲除小鼠来检验SMDC在免疫启动中的体内重要性。我们将创建一个转基因小鼠系，其中CD301b基因的启动子区域，由smdc特异性表达，将用于表达白喉毒素（DT）受体- GFP融合分子。在用DT治疗这些小鼠后，将实现smdc的选择性消耗。本目标将汇集目标1和目标2的知识和进展，并提供上皮细胞、smdc和其他apc在HSV-2先天识别中相互作用的基本见解，从而产生适应性免疫。通过对阴道dc在HSV-2生殖器感染后如何协调产生免疫的基本了解，这些研究将有助于为设计针对生殖器疱疹和其他有害性传播疾病的免疫干预和预防措施奠定重要基础。公共卫生相关性：单纯疱疹病毒-2 （HSV-2）是生殖器疱疹的病原体，是一种非常普遍的性传播感染（仅在美国就有4500万例）。一旦感染，2型单纯疱疹病毒会导致终生无法治愈的衰弱性疾病，目前尚无疫苗。这项拨款申请旨在研究女性生殖器粘膜中的局部树突状细胞如何启动针对HSV-2感染的免疫反应的机制，通过该项目获得的理解将有助于为设计针对生殖器疱疹和其他有害性传播疾病的免疫干预和预防措施奠定重要基础。

DESCRIPTION (provided by applicant): Herpes simplex virus-2 (HSV-2) is one of the most common sexually transmitted infections (STIs) with a prevalence of 45 million in the USA. HSV-2 is transmitted via exposure at the genital mucosal surfaces, leading to the establishment of latency in the sacral ganglia, causing an incurable disease. Although HSV-2- related symptoms can be treated temporarily with antiviral agents, there are no vaccines available for the prevention of this disease. Towards developing an effective HSV-2 vaccine, a clear understanding of the mechanism by which immune responses are generated within the relevant mucosal sites is necessary. Currently, the process of initiation of immune responses within the female genital mucosa is poorly understood. Thus, the goal of the proposed studies is to understand the inductive mechanism of local protective immunity mediated by antigen presenting dendritic cells (DCs) in the female genital tract following infection with HSV-2. In this application, we build on the discoveries made in the first funding period and propose three distinct yet inter-related Aims. In the first Aim, based on our preliminary data demonstrating the requirement for both Toll-like receptor (TLR) and CD4 T help in generating CTL responses following HSV-2 infection, we propose to dissect the mechanisms by which these two signals enable DCs to prime CTL responses against genital herpes infection. Next, based on our demonstration that TLR-mediated recognition of HSV-2 infection by the infected vaginal keratinocytes is necessary for submucosal DCs (SMDCs) to induce robust Th1 immunity in vivo, in the second Aim, we propose to identify the keratinocyte- produced factors responsible for this effect, and to examine their relevance in anti-HSV-2 immunity in vivo. In the final Aim, we propose to examine the in vivo importance of SMDCs in immune priming by generating SMDC inducible-knockout mice. We will create a transgenic mouse line in which the promoter region of the CD301b gene, specifically expressed by the SMDCs, will be used to express diphtheria toxin (DT) receptor- GFP fusion molecule. Upon treatment of such mice with DT, selective depletion of SMDCs will be achieved. This Aim will bring together the knowledge and advances made in Aims 1 & 2 and provide fundamental insights on the interplay between the epithelial cells, SMDCs and other APCs in innate recognition of HSV-2 leading to the generation of adaptive immunity. By providing basic understanding of how vaginal DCs orchestrate the generation of immunity following HSV-2 genital infection, these studies will help to establish critical foundation with which to design immunological interventions and preventative measures against genital herpes and other deleterious STI diseases. PUBLIC HEALTH RELEVANCE: Herpes simplex virus-2 (HSV-2), a causative agent of genital herpes, is a highly prevalent (45 million in the USA alone) sexually transmitted infection. Once acquired, HSV-2 causes a life-long incurable debilitating disease for which no vaccines are currently available. This grant application proposes to examine the mechanism by which local dendritic cells in the female genital mucosa initiate immune responses against HSV-2 infection - the understanding obtained through the project will help to establish critical foundation with which to design immunological interventions and preventative measures against genital herpes and other deleterious sexually transmitted diseases.