Rehman Khaja K, Trucco Massimo, Wang Zhong, Xiao Xiao, Robbins Paul D
Department of Microbiology and Molecular Genetics, University of Pittsburgh School of Medicine, Pittsburgh, Pennsylvania, USA.
Mol Ther. 2008 Aug;16(8):1409-16. doi: 10.1038/mt.2008.116. Epub 2008 Jun 17.
We have demonstrated the ability to deliver and express genes specifically in beta-cells for at least 6 months, using a murine insulin promoter (mIP) in a double-stranded, self-complementary AAV vector (dsAAV8-mIP). In this study, we evaluated the effects of dsAAV8-mIP-mediated delivery of interleukin 4 (mIL-4) to endogenous beta-cells in nonobese diabetic (NOD) mice. In 4-week-old NOD mice, the extent of gene transfer and expression in endogenous beta-cells after ip delivery of dsAAV8-mIP-enhanced green fluorescent protein (eGFP) was comparable to normal BALB/C mice. Further, after IP delivery of dsAAV8-mIP-IL4, expression of mIL-4 was detected in islets isolated from the treated mice and cultured. AAV8-mIP-mediated gene expression of mIL-4 in endogenous beta- cells of 4- and 8-week-old NOD mice prevented the onset of hyperglycemia in NOD mice and reduced the severity of insulitis. Moreover, expression of mIL-4 also maintained the level of CD4(+)CD25(+)FoxP3(+) cells, and adoptive transfer of splenocytes from nondiabetic dsAAV8-mIP-IL-4 mice to NODscid mice was able to block the diabetes induced by splenocytes co-adoptively transferred from nondiabetic dsAAV-mIP-eGFP mice. Taken together, these results demonstrate that local expression of mIL-4 in islets prevents islet destruction and blocks autoimmunity, partly through regulation of T-cell function.
我们已经证明，使用双链、自我互补的腺相关病毒载体（dsAAV8-mIP）中的小鼠胰岛素启动子（mIP），能够在β细胞中特异性递送和表达基因至少6个月。在本研究中，我们评估了dsAAV8-mIP介导的白细胞介素4（mIL-4）递送至非肥胖糖尿病（NOD）小鼠内源性β细胞的效果。在4周龄的NOD小鼠中，腹腔注射dsAAV8-mIP-增强型绿色荧光蛋白（eGFP）后，内源性β细胞中的基因转移和表达程度与正常BALB/C小鼠相当。此外，腹腔注射dsAAV8-mIP-IL4后，在从处理过的小鼠分离并培养的胰岛中检测到了mIL-4的表达。AAV8-mIP介导的mIL-4在4周龄和8周龄NOD小鼠内源性β细胞中的基因表达可预防NOD小鼠高血糖的发生，并减轻胰岛炎的严重程度。此外，mIL-4的表达还维持了CD4(+)CD25(+)FoxP3(+)细胞的水平，并且将非糖尿病dsAAV8-mIP-IL-4小鼠的脾细胞过继转移至NODscid小鼠能够阻断由非糖尿病dsAAV-mIP-eGFP小鼠过继转移的脾细胞诱导的糖尿病。综上所述，这些结果表明，胰岛中mIL-4的局部表达可预防胰岛破坏并阻断自身免疫，部分是通过调节T细胞功能实现的。
