结缔组织生长因子重组干扰载体慢病毒颗粒的构建及其对视网膜血管内皮细胞内源性结缔组织生长因子表达的抑制作用

Construction of connective tissue growth factor recombinant interference vector lentiviral particle and its inhibitory effect on endogenous connective tissue growth factor expression in retinal vascular endothelial cells

目的构建结缔组织生长因子（CTGF）重组干扰载体（shRNA），观察其对视网膜血管内皮细胞内源性CTGF表达的抑制作用。 方法构建人源CTGF shRNA，应用三质粒包装系统获得高滴度的CTGF shRNA慢病毒颗粒。感染视网膜血管内皮细胞，利用干扰载体中的红色荧光标记示踪并筛选慢病毒的最佳感染复数及起效时间。将细胞分为空白对照组（正常培养）、感染对照组（Scramble shRNA病毒感染）及CTGF敲低组（CTGF shRNA病毒感染）。通过Transwell细胞迁移实验观察3组细胞的迁移能力；实时定量聚合酶链反应（PCR）和蛋白免疫印迹法（Western blot）检测3组细胞的结缔组织生长因子（CTGF）、纤连蛋白（FN）、α-平滑肌肌动蛋白（α-SMA）、Ⅰ型胶原蛋白（ColⅠ）的mRNA和蛋白表达。3组间数据比较采用方差分析。 结果CTGF shRNA的最佳感染复数为20，最佳起效时间是72 h。Transwell细胞迁移实验结果显示，CTGF敲低组穿过小孔细胞数较空白对照组及感染对照组明显降低，差异均有统计学意义（F=20.64，P=0.002）。实时定量PCR及Western blot检测结果显示，CTGF敲低组CTGF、FN、α-SMA、ColⅠ mRNA（F=128.83、124.44、144.76、1 374.44，P=0.000、0.000、0.000、0.000）和蛋白表达（F=22.55、41.60、25.73、161.68，P=0.002、0.000、0.001、0.000）较空白对照组、感染对照组明显降低，差异均有统计学意义。 结论成功构建的CTGF shRNA慢病毒颗粒可有效抑制视网膜血管内皮细胞迁移并下调内源性CTGF的表达。

ObjectiveTo construct the connective tissue growth factor （CTGF） recombinant interference vector （shRNA） and observe its inhibitory effect on the expression of endogenous CTGF in retinal vascular endothelial cells. Methods The human CTGF shRNA was constructed and the high-titer CTGF shRNA lentivirus particles was acquired via three-plasmid lentivirus packaging system to infect retinal vascular endothelial cells. The optimal multiplicity and onset time of lentivirus infection were identified by tracing down the red florescent protein in interference vector. The cells were classified into three groups： blank control group, infection control group and CTGF knockdown group. The differences in cells migrating ability was observed through Transwell allay. The mRNA and protein expression of CTGF, fibronectin, α-smooth muscle actin （α-SMA） and collagen Ⅰ （Col Ⅰ） were quantified through real-time PCR testing and Western blot system. Data between the three groups were examined via one-way analysis of variance. ResultsThe result showed that an optimal multiplicity of 20 and onset time of 72 hours were the requirements to optimize lentivirus infection. Transwell allay result showed a contrast in the number of migrated cells in the CTGF knockdown group and that in the blank control group and infection control group （F=20.64, P=0.002）. Real-time PCR testing showed a contrast in related gene expression （CTGF, fibronectin, α-SMA and Col Ⅰ） in the CTGF knocked-down group and that in the blank control group and infection control group （F=128.83, 124.44, 144.76, 1 374.44; P=0.000, 0.000, 0.000, 0.000）. Western blot system showed the statistical significance of the contrasted number of related protein expression （CTGF, fibronectin, α-SMA and Col Ⅰ） in the knockdown group and that in the blank control group （F=22.55, 41.60, 25.73, 161.68; P=0.002, 0.000, 0.001, 0.000）. ConclusionThe success in producing CTGF shRNA lentivirus particle suggests that CTGF shRNA lentivirus can effectively knock down CTGF expression.