Therapeutic Ocular HSV Vaccine in HLA Transgenic Rabbits

描述（由申请人提供）：单纯疱疹病毒1（HSV-1）感染角膜，然后在三叉神经节（TG）的感觉神经元中建立潜伏期。HSV-1的散发性自发再活化引起病毒在泪液中脱落，导致病毒传播给其他个体，并且还可引起复发性疱疹性基质角膜炎（HSK），一种致盲性眼病。我们目前知识的一个主要空白是：“我们如何预防或显著减少泪液中的病毒脱落和由于TG中潜伏病毒的自发再活化引起的HSV诱导的眼部疾病？“HSV特异性CD 8 + T细胞似乎减少了体外诱导的HSV-1在小鼠TG中的再激活。不幸的是，HSV-1在小鼠中的自发再活化极其罕见，因此这些发现与体内HSV-1自发再活化的相关性无法在小鼠中确定。我们现在有一个“人源化的”HLA转基因兔模型的眼部HSV-1，安装“人样”的CD 8 T细胞免疫反应（HLA Tg兔）。在初步研究中，我们发现用来自HSV-1 gD的3个人CD 8 T细胞表位对潜伏感染的HLA Tg兔进行治疗性免疫使自发再活化降低4倍。这种新的动物模型现在将使我们第一次测试这样的假设，即诱导适当的人类T细胞对HSV-1的反应的治疗性疫苗可以减少自发再活化的影响（眼睛中的病毒脱落和HSV诱导的眼部疾病）。我们的具体目标包括：（1）。测试用HSV-1人CD 8 + T细胞表位治疗性免疫可以减少潜伏感染的HLA转基因兔中的自发再活化的假设。携带来自糖蛋白B和D（gB & gD）的人CD 4+和CD 8 + T细胞表位的不同组合的CD 4-CD 8脂肽疫苗将用于免疫潜伏感染的HLA Tg兔。将确定针对眼部病毒脱落（由于自发再活化）和HSV诱导的眼部疾病的保护。 （二）、检验目标1中HLA转基因兔的治疗性疫苗接种诱导的保护性免疫与TG、结膜和/或引流淋巴结中存在效应和记忆CD 8 + T细胞相关的假设。我们将评估体内诱导的HSV特异性和表位特异性CD 8 + T细胞的数量/功能是否与防止泪液和眼部疾病中的自发性病毒脱落相关。我们将评估与保护相关的CD 8 + T细胞机制。 （三）、检验以下假设：在潜伏感染的HLA Tg兔中，减少CD 8 + T细胞将消除疫苗效力，并增加未接种疫苗兔中的自发再活化。 这些研究将提供重要的新的信息，对人类抗原表位的CD 8 + T细胞在免疫控制HSV-1自发再激活的作用。这可能会导致新的范例的发展免疫策略对眼疱疹。 公共卫生相关性：该项目旨在使用新型人类白细胞抗原（HLA）转基因兔模型开发针对眼疱疹（发达国家失明的主要原因）的脂肽治疗疫苗。

DESCRIPTION (provided by applicant): Herpes simplex virus 1 (HSV-1) infects the cornea and then establishes latency in sensory neurons of the trigeminal ganglia (TG). Sporadic spontaneous reactivation of HSV-1 causes shedding of virus in tears leading to spread of virus to other individuals, and can also cause recurrent Herpes Stromal Keratitis (HSK), a blinding ocular disease. A major gap in our current knowledge is: "How can we prevent or significantly reduce virus shedding in tears and HSV-induced ocular disease due to spontaneous reactivation of latent virus in the TG?" HSV-specific CD8+ T-cells appear to decrease in vitro induced HSV-1 reactivation in explanted mouse TG. Unfortunately, spontaneous reactivation of HSV-1 in mice is extremely rare so the relevance of these findings to in vivo HSV-1 spontaneous reactivation cannot be determined in mice. We now have a "humanized" HLA transgenic rabbit model of ocular HSV-1 that mounts "human-like" CD8 T-cell immune responses (HLA Tg rabbits). In a Preliminary Study we found that therapeutic immunization of latently infected HLA Tg rabbits with 3 human CD8 T-cell epitopes from HSV-1 gD decreased spontaneous reactivation 4-fold. This novel animal model will now allow us for the first time to test the hypothesis that a therapeutic vaccine that induces appropriate human T-cell responses to HSV-1 can decrease the effects of spontaneous reactivation (virus shedding in eyes and HSV-induced ocular disease). Our specific Aims include: (1). Test the hypothesis that therapeutic immunization with HSV-1 human CD8+ T-cell epitopes can decrease spontaneous reactivation in latently infected HLA Transgenic rabbits. CD4-CD8 lipopeptide vaccines, bearing different combinations of human CD4+ and CD8+ T cell epitopes from glycoprotein B and D (gB & gD), will be used to immunize latently infected HLA Tg rabbits. Protection against virus shedding in eyes (due to spontaneous reactivation) and HSV-induced ocular disease will be determined. (2). Test the hypothesis that the protective immunity induced by the therapeutic vaccination of HLA Transgenic rabbits in Aim 1 correlates with the presence of effector and memory CD8+ T-cells in the TG, conjunctiva, and/or draining lymph nodes. We will assess whether the number/function of HSV- and epitope- specific CD8+ T cells induced in vivo correlates with protection from spontaneous virus shedding in tears and ocular disease. We will assess the CD8+ T cell mechanism that correlates with protection. (3). Test the hypothesis that decreasing CD8+ T cells in latently infected HLA Tg rabbits will abrogate vaccine efficacy and also increase spontaneous reactivation in unvaccinated rabbits. These studies will provide important new information regarding the role of CD8+ T cells specific to human epitopes in immune control of HSV-1 spontaneous reactivation. This may lead to the development of new paradigms for immunotherapeutic strategies against ocular herpes. PUBLIC HEALTH RELEVANCE: This project is aimed at developing a lipopeptide therapeutic vaccine against ocular herpes (a leading cause of blindness in developed countries) using a novel human leukocyte antigen (HLA) transgenic rabbit model.