HAIRPIN RIBOZYME GENE THERAPY FOR HCV INFECTION

丙型肝炎病毒（HCV）是非甲、非乙型肝炎的主要病因， 这是一个严重的全球性健康问题。我们的长远目标是 开发发夹状核酶（Rz）基因疗法用于治疗HCV 感染Immusol的Rz核心技术，作为 其艾滋病毒项目的成功，是基于工程和 优化发夹Rz基因，其转录的RNA可以特异性地降解 几乎所有不需要的RNA分子。 HCV特别适合于 核酶介导的治疗，因为病毒基因组仅存在于 RNA的形式。HCV仅编码一种初级转录物，因此， 在这个RNA中的任何靶序列都应该消除病毒表达。 Immusol合成了两种靶向HCV（+）链RNA的发夹状核酶 作为HCV感染的潜在治疗剂（Gene Therapy，1996，3： 994）。Immusol还计划靶向负链RNA， HCV复制的重要中间体。这种RNA的降解可能是 更有效，因为其细胞内水平低于 正链RNA。因此，我们提出了一项I期SBIR研究， at：1）合成并优化靶向HCV的有效核酶 正（+）和负（-）链RNA; 2）产生病毒载体 (AV和AAV）表达活性发夹核酶;和3）测试载体- 在肝细胞中降低HCV基因表达的衍生核酶活性 文化实现这三个目标将产生最有效的 用于临床前研究的核酶病毒载体。 拟定商业应用： Immusol计划商业化开发HBV的Rz基因治疗方法 感染 我们将生产和提供表达RZ的病毒载体， 一小瓶然后，这些载体将被提供给周围的医疗中心。 世界上，将进行体内载体介导的基因转移到 患者的肝细胞来对抗HBV病毒。

Hepatitis C virus (HCV) is the major cause of non-A, non-B hepatitis, which is a serious worldwide health problem. Our long term objective is to develop hairpin Ribozyme (Rz) gene therapy for the treatment of HCV infection. Immusol's Rz core technology, developed as a result of the success of its HIV program, is based upon the ability to engineer and optimize hairpin Rz genes whose transcribed RNAs can specifically degrade almost any undesirable RNA molecule. HCV is especially suited for ribozyme-mediated therapy since the viral genome is present exclusively in the form of RNA. HCV encodes only one primary transcript, thus, cleavage of any target sequence within this RNA should abolish virus expression. Immusol has generated two hairpin ribozymes target at HCV (+) strand RNA as potential therapeutic agents for HCV infection (Gene Therapy, 1996, 3: 994). Immusol also plans to target the negative strand RNA that is an essential intermediate in HCV replication. Degradation of this RNA may be more effective, since its intracellular level is lower than that of the positive strand RNA. Therefore, we propose a Phase I SBIR studies aimed at: 1) to synthesize and optimize effective ribozymes that target HCV positive- (+) and negative- (-) strand RNA; 2) to generate viral vectors (AV and AAV) that express active hairpin ribozymes; and 3) to test vector- derived ribozyme activity in reducing HCV gene expression in liver cell culture Achieving these three Aims will generate the most effective ribozyme viral vector(s) for preclinical studies. PROPOSED COMMERCIAL APPLICATION: Immusol plans to commercially develop a Rz gene therapy approach to HBV infection. We will manufacture and provide Rz-expressing viral vectors in a vial. The vectors will then be provided to medical centers around the world that will carry out the in vivo vector-mediated gene transfer into patient liver cells to combat HBV virus.