GENE MODIFICATION OF ADENOVIRUS CAPSID PROTEINS

特定靶细胞的摄取是基因转移的关键第一步。 转移，在大多数系统中受到内源性进入的限制 通过特定的基因转移载体/病毒使用的途径。我们有 成功地改造了Ad 5载体，使其通过 与亚细胞通常使用的不同的高亲和力受体， C组病毒。虽然我们在这方面取得了相当大的进展， 在这一领域，仍然有相当大的必要继续努力， 目标广告载体。如果我们要靶向组织 例如已报道分化良好的气道上皮 缺乏高亲和力和低亲和力受体， C亚群病毒用于进入。 Ad介导的基因转移的基本步骤：1）附着于细胞 通过高亲和力受体（纤维结合CAR，MHC-1），2） 通过五邻体相互作用介导的易化内化 α v β 3，5整联蛋白，和3）内体逃逸，它是α v β 3，5整联蛋白的功能， 主要衣壳蛋白六邻体的构象变化，是 使其成为最有效的基因转移载体 可用向量。这些蛋白质也是先天免疫缺陷病毒的主要靶点。 以及后天免疫系统， 通过Ad载体的基因转移的持续性以及中和 免疫力，这损害了重复管理的有效性， 广告载体。 本项目的重点是对主要衣壳进行基因改造 腺病毒（Ad）的蛋白质：六邻体、纤维和五邻体 基因转移到气道上皮细胞。是我们 这些蛋白质是积极和消极的关键介质， Ad基因转移载体的负面属性和我们的能力， 基因操纵会导致 更有效的基因转移，更大程度的靶细胞 特异性和最后免疫原性降低。发展 在我们的载体中修饰衣壳蛋白的能力将具有直接的 应用于任何广告载体系统，包括“无胆量的载体”， 嵌合病毒载体和Ad载体，用于携带大DNA 分子。

Uptake by a specific target cell is a critical first step in gene transfer, which in most systems is limited by the endogenous entry pathway used by a particular gene transfer vector/virus. We have successfully engineered the Ad 5 vector to bind to a target cell through a different high affinity receptor than that normally used by the sub- group C viruses. Although we have made considerable progress in this area, there is still a considerable need for continuing our efforts to target Ad vectors. This is especially true if we are to target tissues such as well differentiated airway epithelium which have been reported to lack the high affinity as well as low affinity receptors that are used by subgroup C viruses for entry. Steps essential to Ad-mediated gene transfer: 1) attachment to the cell via the high affinity receptor (fiber binding to CAR, MHC-1), 2) facilitated internalization mediated by penton interaction with the alphavbeta3,5 integrins, and 3) endosomal escape which is a function of conformational changes in the major capsid protein hexon, are the aspects of Ad vectors which make them the most efficient gene transfer vector available. These proteins are also the primary targets of innate and acquired immune systems which are responsible for the lack of persistence of gene transfer by Ad vectors as well as the neutralizing immunity which compromises the effectiveness of repeat administration of Ad vectors. The focus of this project is to genetically modify the major capsid proteins of Adenovirus (Ad): hexon, fiber, and penton to the advantage of gene transfer of gene transfer to airway epithelial cells. It is our position that these proteins are the key mediators of both positive and negative attributes of Ad gene transfer vectors and our ability to genetically manipulate to genetically manipulate them will result in more efficient gene transfer, a greater degree of target cell specificity and finally a decreased in imunogenicity. Developing the capacity to modify the capsid proteins in our vectors will have direct application to any Ad vector system, including the "gutless vectors", chimeric virus vectors, and Ad vectors used to piggyback large DNA molecules.