Targeted adenovirus vectors for systemic application

描述(申请人提供)：腺病毒载体(Ad)是美国临床试验中广泛使用的第二大病毒载体组。最近，由于其作为炭疽和其他威胁生命的感染剂的疫苗接种载体的潜力，人们对它的兴趣有所扩大。尽管在体外对Ad与细胞的相互作用有很大的了解，但系统应用的Ad载体的感染性、生物分布和毒性的分子机制仍然知之甚少。我们假设，阻止肝脏介导的Ad从血液中清除应该允许在全身载体应用时改善Ad在循环中的持久性。我们还假设，将有益的衣壳修饰结合在一个载体中，提供载体靶向和血液中的稳定性，是开发基于Ad的安全有效的新疗法的可行途径。最近，我们发现了一种新的凝血因子IX/血液因子依赖的途径，负责在体内通过肝细胞和库普弗细胞捕获腺病毒载体。这一发现为目前的建议奠定了基础，具体目标如下：1.确定Ad5和Ad35纤维结节结构域中负责结合的氨基酸残基以修复。2.制备含有Ad5和/或Ad35纤维的Ad5载体，用于固定和分析其在小鼠模型中的生物分布和循环持久性。3.以小鼠为模型，分析肺癌细胞靶向、FIX结合消融的Ad对靶细胞的转导效率。这些研究将极大地提高我们对体内Ad-宿主相互作用机制的理解，并最终可能导致安全有效的Ad载体的开发，用于治疗广泛的先天和获得性人类疾病。

DESCRIPTION (provided by applicant): Adenovirus vectors (Ad) are the second largest group of viral vectors that are extensively used in clinical trials in the US. The interest in Ad has recently expanded due to its potential as a vector for vaccination against anthrax and other life threatening infection agents. Despite significant knowledge regarding Ad interactions with cells in vitro, the molecular mechanisms governing infectivity, biodistribution and toxicity of systemically applied Ad vectors remain poorly understood. We hypothesize that the prevention of liver-mediated Ad clearance from the blood should allow for the improvement of Ad persistence in the circulation upon systemic vector application. We also hypothesized that combining in one vector the beneficial capsid modifications, which provide both vector targeting and stability in the blood, represents a feasible approach for the development of novel safe and effective therapeutics based on Ad. Recently we discovered a novel coagulation factor IX/blood factor-dependent pathway, responsible for the trapping of adenovirus vector by hepatocytes and Kupffer cells in vivo. This discovery represents a basis for the current proposal with the following specific aims: 1. Identify amino acid residues within Ad5 and Ad35 fiber knob domains responsible for binding to FIX. 2. Develop Ad5-based vectors possessing Ad5 and/or Ad35 fibers ablated for their binding to FIX and analyze their bio-distribution and persistence in circulation in a mouse model. 3. Analyze efficiency of target cell transduction by lung carcinoma cell-targeted, FIX binding-ablated Ad, upon its systemic application in a mouse model. These studies will dramatically improve our understanding of the mechanisms of Ad-host interactions in vivo and may ultimately lead to the development of safe and efficient Ad vectors for the therapy of a wide range of inborn and acquired human diseases.