VACCINIA B5R PROTEIN IN SPREAD IMMUNE EVASION, VACCINES

描述：(摘自申请者的摘要)痘苗病毒作为一种表达系统、基因传递、疫苗接种、 并将其作为病毒致病的模型。然而，一个主要的限制是 利用牛痘病毒载体的能力是致病性的问题。这项研究 牛痘是如何传播和逃避宿主免疫反应的，以及 因此，增强表达的抗原的免疫原性对于 有效利用这一载体系统。痘苗病毒B5R基因编码一种 在胞外病毒粒子膜上发现的42 kDa蛋白及其感染 细胞。在初步研究中，我们已经表明B5R在 病毒通过细胞间传播和远距离传播 细胞外被膜病毒(EEV)的形成。此外，B5R 胞外结构域包含重复单位，与补体调节同源 蛋白质，这可能涉及病毒逃避宿主免疫反应。 然而，我们发现这个结构域和细胞质尾部都是 对于EEV的形成是不必要的，因此可以用作 异源抗原表达。我们假设B5R是一种多功能的 在牛痘的发病、传播和传播中起核心作用的蛋白质 逃避宿主免疫反应；通过修改B5R，这些在体内 牛痘的特性可以改变；B5R可以被操纵来 将异源抗原运输到EEV导致牛痘病毒载体 产生增强的免疫力。这项研究的目的是为了更好地了解 多功能B5R蛋白在痘苗病毒致病中的作用及其开发 异源蛋白的表达，以创造基于牛痘的疫苗 新的生物和抗原呈递能力。要做到这一点，我们将：1) 确定B5R结构域在牛痘发病机制中的功能意义 活体；2)鉴定B5R的补体调节特性；以及3)确定 对新型牛痘疫苗产生的免疫应答 一种HIV抗原与B5R融合。 我们期望这些研究将对牛痘的发病机制有更深入的了解。 以及B5R在传播和逃避宿主免疫反应中的作用； 提供调节牛痘病媒致病性的机制；以及 提供独特的基于牛痘的抗原表达方法， 开发新的疫苗策略。

DESCRIPTION: (Adapted from Applicant's Abstract) Vaccinia virus is the focus of much attention as a vector for expression systems, gene delivery, vaccination, and as a model for viral pathogenesis. However, a major limitation in the ability to utilize vaccinia vectors are concerns about pathogenicity. The study of how vaccinia spreads and evades the host immune response as well as ways to enhance the immunogenicity of expressed antigens, is thus essential for the effective utilization of this vector system. The vaccinia B5R gene encodes a 42-kDa protein found on the membranes of extracellular virions and infected cells. In preliminary studies, we have shown that B5R plays a critical role in cell-to-cell spread and long range dissemination of the virus through the formation of the extracellular enveloped virus (EEV). In addition, the B5R extracellular domain contains repeat units, homologous to complement regulatory proteins, which may be involved in viral evasion of host immune responses. However, we showed that both this domain and the cytoplasmic tail are dispensable for EEV formation and therefore may be utilized as sites for heterologous antigen expression. We hypothesize that B5R is a multifunctional protein that plays a central role in vaccinia pathogenesis, dissemination, and evasion of host immune responses; that by modification of B5R, these in vivo properties of vaccinia can be altered; and that B5R can be manipulated to traffic heterologous antigens to EEV resulting in vaccinia vectors that generate enhanced immunity. The aim of this study is to better understand the multifunctional B5R protein in vaccinia pathogenesis and exploit it for heterologous protein expression in order to create vaccinia-based vaccines with novel biological and antigen presentation capabilities. To do this we will: 1) define the functional significance of B5R domains for vaccinia pathogenesis in vivo; 2) identify the complement regulatory properties of B5R; and 3) Determine the immune responses generated to novel vaccinia vaccines engineered to express an HIV antigen fused to B5R. We anticipate that these studies will give insight into vaccinia pathogenesis and the role of B5R in dissemination and evasion of host immune responses; provide a mechanism of modulating the pathogenicity of vaccinia vectors; and offer unique approaches to vaccinia-based antigen expression that can be exploited for novel vaccine strategies.