Favaro Patricia, Downey Harre D, Zhou J Shangzhen, Wright J Fraser, Hauck Bernd, Mingozzi Federico, High Katherine A, Arruda Valder R
The Children's Hospital of Philadelphia, Philadelphia, Pennsylvania 19104, USA.
Mol Ther. 2009 Jun;17(6):1022-30. doi: 10.1038/mt.2009.56. Epub 2009 Mar 17.
The assessment of the risk of germline transmission of vector-coded sequences is critical for clinical translation of gene transfer strategies. We used rabbit models to analyze the risk of germline transmission of adeno-associated viral (AAV) vectors. Intravenous injection of AAV-2 or AAV-8 resulted in liver-mediated, long-term expression of therapeutic levels of human factor IX (hFIX) in a dose-dependent manner. In high-dose cohorts, AAV-8 resulted in twofold higher levels of circulating hFIX and of vector DNA in liver compared to AAV-2. Vector sequences were found in the semen of all rabbits. The kinetics of vector clearance from semen was dose- and time-dependent but serotype-independent. No late recurrence of AAV-8 sequences was found in the semen over several consecutive cycles of spermatogenesis. In a novel rabbit model, AAV-2 or AAV-8 sequences were detected in the semen of vasectomized animals that lack germ cells. Therefore, structures of the genitourinary (GU) tract, as well as the testis, contribute significantly to vector shedding in the semen. Collectively, data from these two models suggest that the risk of inadvertent germline transmission in males by AAV-8 vectors is low, similar to that of AAV-2, and that AAV dissemination to the semen is in part modulated by host-dependent factors.
评估载体编码序列种系传播的风险对于基因转移策略的临床转化至关重要。我们使用兔模型来分析腺相关病毒（AAV）载体种系传播的风险。静脉注射AAV-2或AAV-8会以剂量依赖的方式导致肝脏介导的人因子IX（hFIX）治疗水平的长期表达。在高剂量组中，与AAV-2相比，AAV-8导致肝脏中循环hFIX和载体DNA水平高出两倍。在所有兔子的精液中均发现了载体序列。载体从精液中清除的动力学是剂量和时间依赖性的，但与血清型无关。在连续几个精子发生周期中，精液中未发现AAV-8序列的晚期复发。在一个新的兔模型中，在缺乏生殖细胞的输精管切除动物的精液中检测到了AAV-2或AAV-8序列。因此，泌尿生殖（GU）道以及睾丸的结构对精液中的载体脱落有显著影响。总体而言，这两个模型的数据表明，AAV-8载体在男性中意外种系传播的风险较低，与AAV-2相似，并且AAV向精液中的传播部分受宿主依赖性因素调节。
