诱导表达人活性型颗粒酶B的Hela细胞系的建立

Establishment of Hela cell line inducibly expressing human active granzyme B

目的 :构建人颗粒酶B基因的可诱导表达载体 ,并将其在Hela细胞中诱导表达 .方法 :用PCR法获取人活性型颗粒酶B基因序列 ,克隆入pIND诱导表达载体中。将其与辅助质粒pVgRXR通过脂质体法共转染Hela细胞后 ,用G4 18和zeocin筛选建系。通过免疫细胞化学染色法 ,确定蜕皮激素A最佳的诱导浓度及诱导时间 ,并通过MTT比色法检测及细胞骨架染色等方法观察 ,表达的活性型颗粒酶B对Hela细胞形态和生长的影响。结果 :获得可诱导表达人活性型颗粒酶B基因的Hela细胞系。免疫细胞化学染色表明 ,30 μmol/L蜕皮激素诱导 5d时目的蛋白表达最强 ,同时观察到Hela细胞的形态发生变化 ,出现多核大细胞及固缩小细胞 ,并且细胞生长受到抑制。骨架分析进一步显示 ,多核大细胞的骨架发生异常。结论 :活性型颗粒酶B的可诱导表达系统的建立 。

AIM: To construct inducible expression vector for human granzyme B gene and express it in Hela cell line. METHODS: Human active granzyme B gene was obtained by PCR and cloned into the inducible expression vector pIND. The resulting expression vector, together with a helper plasmid pVgRXR, was stably transfected into Hela cells using Lipofectamine 2000. The transfected cells were selected in medium containing G418 and zeocin. The resistant cells were induced with ponasterone A, and the optimal concentration of ponasterone A and time of induction were determined by immunocytochemical staining. Then the effects of the expressed granzyme protein on Hela cells were detected by MTT colorimetry and cytoskeletal staining. RESULTS: The Hela cells that inducibly expressed human active granzyme B were obtained. Induction with 30 μmol/L ponasterone A for 5 days caused the strongest expression of granzyme B. The induced cells appeared as either multinucleate giant cells or pyknotic small cells, and their growth was inhibited. Further analysis demonstrated cytoskeletal abnormality of multinucleate giant cells. CONCLUSION: The establishment of inducible expression system for active granzyme B lays the foundation for further research on biological function of granzyme B.