Large-scale molecular characterization of adeno-associated virus vector integration in mouse liver
Large-scale molecular characterization of adeno-associated virus vector integration in mouse liver
复制标题
DOI：
10.1128/jvi.79.6.3606-3614.2005
复制
发表时间：
2005-03-01
影响因子：
5.4
通讯作者：
Kay, MA
中科院分区：
文献类型：
--
作者：
Nakai, H;Wu, XL;Kay, MA
重组腺相关病毒（rAAV）载体有望用于基因治疗。尽管载体基因组的染色体整合频率较低，但最近的研究引起了对rAAV整合风险的担忧，因为整合优先发生在基因中并伴随染色体缺失，这可能导致功能丧失插入诱变。在这里，通过分析347 rAAV在小鼠中的整合，我们阐明了rAAV整合的新功能：整合热点的存在和整合附近的基因调控序列的强烈偏好。最突出的热点是rRNA基因重复序列中的无害染色体小生境，而近一半的整合落在转录起始位点或CpG岛附近，这表明通过载体整合激活侧翼细胞疾病基因的可能性，类似于逆转录病毒功能获得性插入诱变。可能的癌症相关基因被rAAV整合以3.5%的频率命中。此外，关于载体基因组的218个整合位点和602个断点处的染色体变化的信息提供了载体末端重复序列和宿主染色体DNA在整合过程中如何连接的线索。因此，本研究提供了新的见解rAAV介导的插入突变的风险和rAAV整合的机制。
Recombinant adeno-associated virus (rAAV) vector holds promise for gene therapy. Despite a low frequency of chromosomal integration of vector genomes, recent studies have raised concerns about the risk of rAAV integration because integration occurs preferentially in genes and accompanies chromosomal deletions, which may lead to loss-of-function insertional mutagenesis. Here, by analyzing 347 rAAV integrations in mice, we elucidate novel features of rAAV integration: the presence of hot spots for integration and a strong preference for integrating near gene regulatory sequences. The most prominent hot spot was a harmless chromosomal niche in the rRNA gene repeats, whereas nearly half of the integrations landed near transcription start sites or CpG islands, suggesting the possibility of activating flanking cellular disease genes by vector integration, similar to retroviral gain-of-function insertional mutagenesis. Possible cancer-related genes were hit by rAAV integration at a frequency of 3.5%. In addition, the information about chromosomal changes at 218 integration sites and 602 breakpoints of vector genomes have provided a clue to how vector terminal repeats and host chromosomal DNA are joined in the integration process. Thus, the present study provides new insights into the risk of rAAV-mediated insertional mutagenesis and the mechanisms of rAAV integration.