血管内皮生长因子基因在人胚胎胰岛干细胞中的表达

目的 构建含血管内皮生长因子(VEGF)基因的慢病毒载体,转染人胚胎来源的胰岛干细胞(hPSC),探讨VEGF在胰岛干细胞中的体外表达水平及其影响因素.方法 将VEGF基因克隆入慢病毒载体,利用293T细胞包装出病毒,按拷贝数分别为2、5、10转染胰岛干细胞,测定不同转染组VEGF的分泌水平.结果 含VEGF的病毒上清可以在体外培养条件下成功转染胰岛干细胞,经潮霉素筛选3 d后,对照组及拷贝数分别为2、5、10的转染组每1×106个细胞每小时VEGF的分泌量分别为(60.3±13.4)、(1622.0±302.0)、(2270.0±340.0)、(3090.0±465.0)ng/L.对照组与转染组间(P＜0.05)以及各转染组之间差异有统计学意义(P＜0.05).结论 含VEGF的慢病毒载体可以成功转染人胚胎来源的胰岛干细胞,使其持续高表达VEGF,通过改变转染拷贝数可在一定水平上控制VEGF的分泌水平.

Abstract：

Objective To transfect vascular endothelial growth factor (VEGF) gene into human pancreatic stem cells (hPSC) by lentiviral vectors. Methods VEGF gene was sub-cloned into the lentiviral transfer vectors which also encoded hygromycin gene. The recombinant lentiviral vectors were packaged by 293T cells through three plasmids transient co-transfection method using standard lipofectamine reagent.The viral titers were tested by transfecting 293T cells. hPSC were transducted under different multiplicity of infection (MOI). VEGF secretion level was tested by enzyme linked immunosorbent assay (ELISA). Results Lentiviral vectors encoding VEGF and hygromycin resistance gene were constructed. Using lentiviral vectors encoding VEGF, we successfully transfected hPSC, and the transfected hPSC expressed VEGF continuously. On the day 3 after screening by hygromycin, the content of VEGF secreted by 1 × 106 cells per h was (60. 3 ± 13.4), ( 1622.0 ±302. 0), (2270. 0 ±340. 0), (3090. 0 ±465. 0) ng/L respectively when MOI was 0, 2, 5 and 10. The results indicated that VEGF expression was influenced by MOI ( P ＜ 0. 05 ).Conclusion Lentiviral vectors encoding VEGF and hygromycin resistance gene were constructed and could be used to transfect human pancreatic stem cells successfully.

Construction of vascular endothelial growth factor encoding lentiviral vector and its expression in human pancreatic stem cells

Objective To transfect vascular endothelial growth factor (VEGF) gene into human pancreatic stem cells (hPSC) by lentiviral vectors. Methods VEGF gene was sub-cloned into the lentiviral transfer vectors which also encoded hygromycin gene. The recombinant lentiviral vectors were packaged by 293T cells through three plasmids transient co-transfection method using standard lipofectamine reagent.The viral titers were tested by transfecting 293T cells. hPSC were transducted under different multiplicity of infection (MOI). VEGF secretion level was tested by enzyme linked immunosorbent assay (ELISA). Results Lentiviral vectors encoding VEGF and hygromycin resistance gene were constructed. Using lentiviral vectors encoding VEGF, we successfully transfected hPSC, and the transfected hPSC expressed VEGF continuously. On the day 3 after screening by hygromycin, the content of VEGF secreted by 1 × 106 cells per h was (60. 3 ± 13.4), ( 1622.0 ±302. 0), (2270. 0 ±340. 0), (3090. 0 ±465. 0) ng/L respectively when MOI was 0, 2, 5 and 10. The results indicated that VEGF expression was influenced by MOI ( P ＜ 0. 05 ).Conclusion Lentiviral vectors encoding VEGF and hygromycin resistance gene were constructed and could be used to transfect human pancreatic stem cells successfully.