TLS9a核酸适配体对小鼠肝癌细胞的靶向作用研究

Targeting effect of TLS9a nucleic acid aptamer on mice hepatic cancer cells

目的探讨TLS9a核酸适配体对小鼠肝癌细胞的靶向作用。方法制备马来酰亚胺修饰的装载阿霉素的脂质体(liposome),合成FITC荧光及巯基修饰的TLS9a核酸适配体,并将其耦联到脂质体表面。紫外分光光度法检测阿霉素包封率。动态光散射法(DLS)测纳米粒子粒径大小及电位分布,倒置荧光显微镜观察小鼠肝癌细胞对阿霉素摄入及用流式细胞技术检测平均荧光强度,评估小鼠肝癌细胞对药物摄入量。四甲基偶氮唑蓝(MTT)法检测细胞活性。结果流式细胞术检测TLS9a核酸适配体与BNL.1ME.A.7R.1小鼠肝癌细胞结合率为54.1%,TLS9a耦联的脂质体平均粒径分布在(116.0±5.0)nm。TLS9aliposome/DOX在pH 5.0的环境中可以快速释放化疗药物DOX,72h药物释放量超过70%。TLS9a-liposome/DOX在体外能够有效抑制小鼠肝癌细胞BNL.1ME.A.7R.1生长。结论 TLS9a核酸适配体可以特异性与小鼠肝癌细胞BNL.1ME.A.7R.1结合,可用于检测小鼠肝癌细胞。

Objective To investigate the targeting effect of TLS9a nucleic acid aptamer on mice hepatic cancer cells. Methods The tiposome modified with maleimide and loading doxorubicin（DOX） was prepared, then TLSga nucleic acid aptamer modified by FITC fluorescence and sulfydryl was synthesized,which was coupled to the liposome surface. The entrapment efficiency of DOX was detected by UV spectrophotometry. The dynamic light scattering（DLS） was applied to measure the particle size of nanoparti- cles and the potential distribution. The uptake of DOX in mice hepatic cancer ceils was detected by the Nikon inverted microscope and the mean fluorescence intensity of liposome/DOX and TLSga -liposome/DOX was detected by flow cytometry. The Cells activity was detected by MTT. Results Flow cytometry assay showed that the binding rate of TLSga nucleic acid aptamer with BNL. 1ME. A. 7R. 1 mice hepatic cancer cells was 54.1 %. TLSga-liposome particle size distribution was in （116.0±5.0）nm. TLSga-liposome/ DOX released DOX quickly at pH 5.0, and the release amount in 72 h was more than 70 % of the total release amount. TLSga-lipo- some/DOX effectively inhibited the growth of mice hepatic cancer ceils BNL. 1ME. A. 7R. 1. Conclusion TLSga nucleic acid aptam- er could specifically combined with mice hepatic cancer ceils BNL. 1ME. A. 7R. 1 ,which could be used to detect mice hepatic cancer cells.