Creation of immune 'stealth' genes for gene therapy through fusion with the Gly-Ala repeat of EBNA-1
Creation of immune 'stealth' genes for gene therapy through fusion with the Gly-Ala repeat of EBNA-1
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DOI：
10.1038/sj.gt.3302098
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发表时间：
2003-11-01
期刊：
影响因子：
5.1
通讯作者：
Hoeben, RC
中科院分区：
文献类型：
--
作者：
Ossevoort, M;Visser, BMJ;Hoeben, RC
基因治疗方案的一个主要障碍是 T 细胞介导的转基因表达细胞的破坏。因此，需要新的方法来防止转导细胞的快速清除。我们利用 Epstein-Barr 病毒核抗原 1 的 Gly-Ala 重复 (GAr) 结构域，因为 GAr 可以防止细胞毒性 T 淋巴细胞表位的生成。在这里，我们展示了与 GAr 融合的三种不同的酶（即编码 β-半乳糖苷酶的大肠杆菌 LacZ 基因、萤火虫荧光素酶和 HSV1 胸苷激酶）保留了其功能。此外，将 GAr 与 β-半乳糖苷酶连接成功地阻止了 β-半乳糖苷酶特异性 CTL 对表达 GAr-LacZ 的细胞的识别。尽管如此，用 GAr-LacZ 腺病毒或表达 GAr-LacZ 的同种异体细胞系进行疫苗接种会导致 β-gal 特异性 CTL 的诱导。这表明GAr结构域不会抑制抗原的交叉呈递，而仅影响内源合成蛋白质的分解。这些数据展示了如何利用 GAr 结构域通过隐藏转基因产物免受 CTL 介导的免疫攻击来创建免疫“隐形”基因。
A major obstacle in gene-therapy protocols is T-cell-mediated destruction of transgene-expressing cells. Therefore new approaches are needed to prevent rapid clearance of transduced cells. We exploited the Gly-Ala repeat (GAr) domain of the Epstein - Barr virus nuclear antigen-1, since the GAr prevents cytotoxic T-lymphocyte-epitope generation. Here we show that three different enzymes ( viz. the E. coli LacZ gene encoded beta-galactosidase, firefly luciferase, and HSV1 thymidine kinase) fused with the GAr retained their function. Moreover, linking GAr with beta-galactosidase successfully prevented recognition of GAr-LacZ-expressing cells by beta-galactosidase- specific CTL. Nonetheless, vaccination with a GAr-LacZ adenovirus or with an allogeneic cell line expressing GAr-LacZ resulted in the induction of beta-gal-specific CTL. This demonstrates that the GAr domain does not inhibit crosspresentation of antigens, but only affects breakdown of endogenously synthesized proteins. These data demonstrate how the GAr domain can be exploited to create immuno 'stealth' genes by hiding transgene products from CTL-mediated immune attack.