Gene transfer into human hematopoietic progenitor cells with an episomal vector carrying an S/MAR element
Gene transfer into human hematopoietic progenitor cells with an episomal vector carrying an S/MAR element
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DOI：
10.1038/sj.gt.3302593
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发表时间：
2006-01-01
期刊：
影响因子：
5.1
通讯作者：
Athanassiadou, A
中科院分区：
文献类型：
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作者：
Papapetrou, EP;Ziros, PG;Athanassiadou, A
异常态维持的自我复制系统为基因治疗应用提供了有吸引力的替代工具。最近对染色体支架/基质附着区(S/MARS)介导遗传元件上体维持的能力的深入研究，使得一个小的环状上体载体的功能独立于病毒编码的蛋白质。在这项研究中，我们研究了该载体Pepi-EGFP在造血祖细胞系和原代人类细胞中介导基因转移的潜力。PEPI-EGFP在人类细胞系K562以及原代人成纤维细胞样细胞中，即使在非选择性条件下也能保持和持续表达EGFP。相比之下，在小鼠红白血病细胞系MEL中，转基因表达通过组蛋白去乙酰化而沉默，尽管载体具有附着体的持久性。来自转染人脐血CD34(+)细胞的造血半固体细胞集落表达EGFP，尽管表达水平较低。4周后，载体保留在大约1%的子代细胞中。我们的结果首次证明了基于S/MAR的重组质粒可以在原代人类细胞中作为稳定的内切体发挥作用，支持转基因的长期表达。但是，它们并不在所有单元格类型中显示通用行为。
Episomally maintained self-replicating systems present attractive alternative vehicles for gene therapy applications. Recent insights into the ability of chromosomal scaffold/matrix attachment regions (S/MARs) to mediate episomal maintenance of genetic elements allowed the development of a small circular episomal vector that functions independently of virally encoded proteins. In this study, we investigated the potential of this vector, pEPI-eGFP, to mediate gene transfer in hematopoietic progenitor cell lines and primary human cells. pEPI-eGFP was episomally maintained and conferred sustained eGFP expression even in nonselective conditions in the human cell line, K562, as well as in primary human fibroblast-like cells. In contrast, in the murine erythroleukemia cell line, MEL, transgene expression was silenced through histone deacetylation, despite the vector's episomal persistence. Hematopoietic semisolid cell colonies derived from transfected human cord blood CD34(+) cells expressed eGFP, albeit at low levels. After 4 weeks, the vector is retained in approximately 1% of progeny cells. Our results provide the first evidence that S/MAR-based plasmids can function as stable episomes in primary human cells, supporting long-term transgene expression. However, they do not display universal behavior in all cell types.