Shiau Ai-Li, Liu Pu-Ste, Wu Chao-Liang
Department of Microbiology and Immunology, National Cheng Kung University Medical College, Tainan, Taiwan.
J Virol. 2005 Jan;79(1):193-201. doi: 10.1128/JVI.79.1.193-201.2005.
Recombinant adeno-associated virus (rAAV) vectors have many advantages for gene therapeutic applications compared with other vector systems. Several methods that use plasmids or helper viruses have been reported for the generation of rAAV vectors. Unfortunately, the preparation of large-scale rAAV stocks is labor-intensive. Moreover, the biological titration of rAAV is still difficult, which may limit its preclinical and clinical applications. For this study, we developed a novel strategy to generate and biologically titrate rAAV vectors. A recombinant pseudorabies virus (PrV) with defects in its gD, gE, and thymidine kinase genes was engineered to express the AAV rep and cap genes, yielding PS virus, which served as a packaging and helper virus for the generation of rAAV vectors. PS virus was useful not only for generating high-titer rAAV vectors by cotransfection with an rAAV vector plasmid, but also for amplifying rAAV stocks. Notably, the biological titration of rAAV vectors was also feasible when cells were coinfected with rAAV and PS virus. Based on this strategy, we produced an rAAV that expresses prothymosin alpha (ProT). Expression of the ProT protein in vitro and in vivo mediated by rAAV/ProT gene transfer was detected by immunohistochemistry and a bioassay. Taken together, our results demonstrate that the PrV vector-based system is useful for generating rAAV vectors carrying various transgenes.
与其他载体系统相比,重组腺相关病毒(rAAV)载体在基因治疗应用方面具有许多优势。已经报道了几种使用质粒或辅助病毒产生rAAV载体的方法。不幸的是,大规模制备rAAV储备是一项劳动密集型工作。此外,rAAV的生物学滴定仍然困难,这可能会限制其临床前和临床应用。在本研究中,我们开发了一种产生和生物学滴定rAAV载体的新策略。构建了一种在其gD、gE和胸苷激酶基因上有缺陷的重组伪狂犬病病毒(PrV),使其表达AAV的rep和cap基因,产生PS病毒,该病毒用作产生rAAV载体的包装和辅助病毒。PS病毒不仅可用于通过与rAAV载体质粒共转染产生高滴度rAAV载体,还可用于扩增rAAV储备。值得注意的是,当细胞用rAAV和PS病毒共感染时,rAAV载体的生物学滴定也是可行的。基于此策略,我们制备了一种表达前胸腺素α(ProT)的rAAV。通过免疫组织化学和生物测定法检测了rAAV/ProT基因转移介导的ProT蛋白在体外和体内的表达。综上所述,我们的结果表明基于PrV载体的系统可用于产生携带各种转基因的rAAV载体。