VARICELLA ZOSTER VIRUS--T CELL/SKIN TROPISMS AND IMMUNIT

水痘带状疱疹病毒--T细胞/皮肤向性和免疫

• 批准号: 2907947
• 负责人: Ann Arvin
• 金额: $ 29.82万
• 依托单位: STANFORD UNIVERSITY
• 依托单位国家: 美国
• 财政年份: 1994
• 资助国家: 美国
• 起止时间: 1994-08-01 至 2004-07-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/2907947
• 关键词: Herpesviridae vaccine; MHC class I antigen; MHC class II antigen; SCID mouse; T lymphocyte; antigen presentation; cell migration; cellular immunity; chickenpox; epitope mapping; flow cytometry; gene mutation; glycoproteins; host organism interaction; human subject; hybridomas; immunogenetics; immunologic memory; live vaccine; organ culture; shingles; skin; varicella zoster virus; virus protein; virus replication

Varicella-zoster virus (VZV) causes varicella and herpes zoster. Our goal is to improve knowledge about how this common pathogen causes disease and about protection provided by natural and vaccine-induced immunity. Glycoproteins are likely to be host range determinants for T cells and skin, which are critical target cells during VZV infection. Our focus is on glycoproteins, gI (ORF67) and gE (ORF68). The effect of gI or gE mutations made in cosmids, on VZV replication will be determined in vitro. Infectivity for human CD4+ and CD8+ T cells or skin will be assessed in vivo in the SCIDhu mouse model of VZV pathogenesis, which reveals critical roles for VZV proteins that are completely dispensable in tissue culture. T cell tropism will also be investigated in thymic organ cultures and II23 cells, a CD4+ T cell hybridoma, using green fluorescent protein (gfp)-labeled VZV. VZV gI and gE effects on epithelial cells will be evaluated in MDCK cells. The vaccine strain, V-Oka, will be compared with its parent, P-Oka, to determine whether gE or gI mutations explain V-Oka attenuation. VZV infects T cells in the naive host and spreads before VZV specific immunity is induced. We have found that VZV interferes with cell surface expression of major histocompatibility (MHC) class I and class II. Our goals are to identify viral immunomodulatory proteins that allow VZV to escape from immune surveillance and to determine whether skin homing receptors facilitate transport of infected T cells to skin. Whether these mechanisms function at skin sites during natural infection will be determined in biopsies from acute varicella lesions. Rapid acquisition of VZV specific T cell responses correlates with mild varicella and maintenance of latency. We propose to address important questions about adaptive VZV immunity with new methods to measure CD4+ and CD8+ T cell responder frequencies against dominant viral proteins, gE and the immediate early tegument/transactivating protein, IE62. We will examine differences in protection afforded by natural and vaccine-induced immunity, diminished immunogenicity of varicella vaccine in adults, and declining VZV T cell responses with aging. Quantitative comparisons of CD4+ and CD8+ recognition of gE and IE62 protein and peptides will be made using intracellular cytokine assays. Peptides appropriate for synthesis as MHC class I and class II tetramers will be identified and used to enumerate VZV specific responder T cells in CD4+ and CD8+ subsets. These parallel investigations of VZV pathogenesis and immunity are directly linked by their practical relevance for improving live attenuated varicella vaccines.

水痘带状疱疹病毒（VZV）引起水痘和带状疱疹。我们的目标是提高对这种常见病原体如何引起疾病以及自然免疫和疫苗诱导免疫提供的保护的了解。 糖蛋白可能是 T 细胞和皮肤的宿主范围决定因素，而 T 细胞和皮肤是 VZV 感染期间的关键靶细胞。 我们的重点是糖蛋白、gI (ORF67) 和 gE (ORF68)。 粘粒中产生的 gI 或 gE 突变对 VZV 复制的影响将在体外测定。 将在 VZV 发病机制的 SCIDhu 小鼠模型中体内评估人类 CD4+ 和 CD8+ T 细胞或皮肤的感染性，这揭示了在组织培养中完全可有可无的 VZV 蛋白的关键作用。 还将使用绿色荧光蛋白 (gfp) 标记的 VZV 在胸腺器官培养物和 II23 细胞（一种 CD4+ T 细胞杂交瘤）中研究 T 细胞向性。 VZV gI 和 gE 对上皮细胞的影响将在 MDCK 细胞中进行评估。 疫苗株 V-Oka 将与其亲本 P-Oka 进行比较，以确定 gE 或 gI 突变是否解释了 V-Oka 减毒。 VZV 感染初始宿主的 T 细胞并在 VZV 特异性免疫被诱导之前传播。我们发现 VZV 干扰 I 类和 II 类主要组织相容性 (MHC) 的细胞表面表达。 我们的目标是鉴定使水痘带状疱疹病毒逃避免疫监视的病毒免疫调节蛋白，并确定皮肤归巢受体是否促进受感染的 T 细胞转运至皮肤。 这些机制在自然感染期间是否在皮肤部位发挥作用将通过急性水痘病变的活检来确定。 VZV 特异性 T 细胞反应的快速获得与轻度水痘和潜伏期的维持相关。 我们建议通过新方法测量针对优势病毒蛋白 gE 和立即早期被膜/反式激活蛋白 IE62 的 CD4+ 和 CD8+ T 细胞反应频率来解决有关适应性 VZV 免疫的重要问题。我们将研究自然免疫和疫苗诱导免疫提供的保护差异、成人水痘疫苗免疫原性的降低以及随着年龄增长而降低的 VZV T 细胞反应。将使用细胞内细胞因子测定对 gE 和 IE62 蛋白和肽的 CD4+ 和 CD8+ 识别进行定量比较。 适合合成为 MHC I 类和 II 类四聚体的肽将被鉴定并用于计数 CD4+ 和 CD8+ 亚群中的 VZV 特异性应答 T 细胞。 这些对水痘带状疱疹病毒发病机制和免疫的平行研究与改进水痘减毒活疫苗的实际相关性直接相关。