Project 2: Virologic determinants of cCMV

摘要-项目2：胎儿RhCMV传播的病毒决定因素 人巨细胞病毒(HCMV)是新生儿先天性疾病的主要感染原因， 开发治疗和预防措施需要对病毒有更好的了解 在CMV-天真和CMV免疫个体中允许胎儿传播的决定因素。因为人巨细胞病毒是高度 利用相应动物巨细胞病毒先天感染的物种受限的动物模型来研究 先天性感染。非人灵长类动物模型的最新进展首次使胎儿 由一种与人类高度同源的病毒在解剖上与人类非常相似的宿主中传播 人巨细胞病毒。因此，该项目的目标是使用该模型来识别和表征病毒的决定因素。 促进胎儿传播最终要支持制定具体的对策。具体来说， 我们将检查胎儿传播是否与病毒血症和病毒在孕妇中的传播有关。 女性。我们将进一步研究病毒细胞嗜性在胎儿感染中的作用，并检验以下假设 抗病毒抗体的疗效受到病毒Fc受体的限制。使基因操作成为可能 为了解决这些问题，我们产生了细菌人工染色体(BAC) 代表低传代分离株的克隆，证实了BAC来源的RhCMV的胎儿传播。 利用这个BAC，我们将利用我们观察到的RhCMV缺乏免疫显性主要 被膜蛋白pp65在RhCMV-naive中的复制和传播显著增加 动物研究病毒血症和病毒传播在胎儿传播中的作用(目标1)。我们将进一步 实验解决细胞趋向性决定五聚体糖蛋白复合体的作用 GH/GL/UL128/UL130/UL131a在母婴传播中(目标2)。五聚体复合体目前是一个 疫苗开发的主要目标，但初步数据出人意料地显示，传播增加 缺乏这种复合体的病毒。最后，我们将确定病毒Fc受体是否限制了 高免疫球蛋白治疗以限制病毒传播(目标3)。该项目将同时受益于 影响项目1中描述的研究，并需要所有四个核心的服务。我们预计这将是 该项目将影响预防和治疗性巨细胞病毒疫苗的设计，并将揭示新的 改进基于抗体的治疗的方法。

ABSTRACT – Project 2: Viral determinants of fetal RhCMV transmission Human cytomegalovirus (HCMV) is the leading infectious cause of congenital disease in newborns, and the development of treatments and preventative measures requires a better understanding of the viral determinants enabling fetal transmission in CMV-naïve and CMV-immune individuals. Since HCMV is highly species-restricted, animal models of congenital infection by the corresponding animal CMVs are used to study congenital infection. Recent advances in non-human primate models for the first time enable the study of fetal transmission in a host that is anatomically very similar to humans by a virus that is highly homologous to HCMV. The goal of this project is therefore to use this model to identify and characterize viral determinants facilitating fetal transmission to ultimately support the development of specific countermeasures. Specifically, we will examine whether fetal transmission correlates with viremia and viral dissemination in the pregnant female. We will further examine the role of viral cell tropism in fetal infection and examine the hypothesis that the efficacy of antiviral antibodies is limited by viral Fc receptors. To enable the genetic manipulation of RhCMV that is required to address these questions we generated a bacterial artificial chromosome (BAC) clone representative of a low passage isolate and demonstrated fetal transmission of BAC-derived RhCMV. Using this BAC we will take advantage of our observation that RhCMV lacking the immunodominant major tegument protein pp65 displayed dramatically increased replication and dissemination in RhCMV-naïve animals to examine the role of viremia and viral dissemination in fetal transmission (Aim 1). We will further experimentally address the role of the cell tropism-determining pentameric glycoprotein complex gH/gL/UL128/UL130/UL131A in maternal/fetal transmission (Aim 2). The pentameric complex is currently a major target for vaccine development, but preliminary data unexpectedly revealed increased transmission of virus lacking this complex. Finally, we will determine whether viral Fc-Receptors limit the efficacy of hyperimmunoglobulin treatment to limit viral dissemination (Aim 3). This project will both benefit from and impact the studies described in Project 1 and require the services of all four cores. We anticipate that this project will impact the design of prophylactic and therapeutic CMV vaccines and that it will reveal novel approaches to improve antibody-based therapy.