Ad5 Fiber and Penton mts: Influence on immune activation

描述(由申请人提供)： 我们的实验室长期以来一直对腺病毒、Ad载体的生物学以及Ad衣壳蛋白如何在基因转导和免疫激活中发挥作用感兴趣。目前的建议解决了免疫系统如何在宿主对感染的最早反应阶段识别病毒的问题。从拟议的研究中获得的知识将使我们能够产生具有“隐形”特性的新的病毒载体，同时，将突出通常导致强大的炎症和对野生型Ad的免疫的机制。隐形载体将允许更安全的基因转移和更长时间的转移基因表达。拟议的研究基于我们的初步数据产生的一个新的假设：两种主要类型的抗原提呈细胞(APC)-树突状细胞(DC)和巨噬细胞(MO)-调节宿主对Ad的免疫反应的性质和大小；APC通过Ad的潜在抗原和表位的有限子集检测病毒；主要表位位于衣壳蛋白中，但两种类型的APC不同；DC的主要表位存在于五角体衣壳蛋白中；MO的主要表位存在于纤维衣壳蛋白中。我们已经构建了一组新的在五角体和纤维中突变的Ad载体，这将使我们能够检验这一假说。这些研究的结果不仅将对基因转移应用具有实际意义，而且将为免疫系统识别病毒的早期阶段的基本方面提供新的线索。

DESCRIPTION (provided by applicant): Our laboratory has had a long-standing interest in the biology of Adenovirus, Ad vectors and how Ad capsid proteins contribute to gene transduction and immune activation. The current proposal addresses the question of how the immune system recognizes a virus at the earliest stages of the host response to infection. The knowledge gained from the proposed studies will allow us to generate new viral vectors that have "stealth" characteristics, and at the same time, will highlight the mechanisms normally resulting in robust inflammation and immunity against wild type Ad. Stealth vectors will allow safer gene transfer and more prolonged expression of transferred genes. The proposed studies are based on a new hypothesis arising from our preliminary data: That two of the major types of antigen presenting cells (APCs)-dendritic cells (DC) and macrophages (MO)-regulate the nature and magnitude of the host immune response to Ad; that APC's detect the virus through a restricted subset of Ad's potential antigens and epitopes; that the dominant epitopes reside in capsid proteins, yet are different for the two types of APC; that the dominant epitope for DC resides in the penton capsid protein; and that the dominant epitope for MO resides in the fiber capsid protein. We have constructed a new set of Ad vectors mutated in penton and fiber that will allow us to test this hypothesis. The results of these studies will not only hold practical implications for gene transfer applications, but will shed new light on fundamental aspects of the earliest phases of viral recognition by the immune system.