Targeted adenovirus vectors for systemic application

描述（由申请人提供）：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。对Ad的兴趣最近扩大了，因为它有可能作为针对炭疽和其他威胁生命的感染因子接种疫苗的媒介。尽管对体外Ad与细胞的相互作用有重要的了解，但控制系统应用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，预防肝介导的Ad从血液中清除应该允许在系统载体应用后改善Ad在循环中的持久性。我们还假设，在一个载体中结合有益的衣壳修饰，既提供载体靶向性又提供血液稳定性，代表了开发基于Ad的新型安全有效的治疗方法的可行方法。最近，我们发现了一种新的凝血因子IX/血液因子依赖通路，负责肝细胞和库普弗细胞在体内捕获腺病毒载体。这一发现为当前具有以下具体目标的建议奠定了基础：鉴定Ad5和Ad35纤维旋钮结构域中与FIX结合的氨基酸残基。2. 开发Ad5载体，将Ad5和/或Ad35纤维与FIX结合，并在小鼠模型中分析其生物分布和循环持久性。3. 分析肺癌细胞靶向的FIX结合消融Ad在小鼠模型中的系统应用对靶细胞转导的效率。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，并可能最终导致开发安全有效的Ad载体，用于治疗广泛的先天性和获得性人类疾病。

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.