本研究利用基因治疗方法中的反义技术,通过脂质体包裹反义胰岛素样生长因子-I(IGF-I)基因导入人7402肝癌细胞株,研究肿瘤细胞表面MHC分子的表达和其对LAK细胞杀伤的敏感性。结果表明,反义IGF-I基因转染的人7402肝癌细胞,经潮霉素筛选后,Northern Blot分析显示反义IGF-I RNA表达阳性,MHC Ⅰ类和Ⅱ类抗原的表达水平高于亲本7402细胞。LAK细胞对反义IGF-I基因转染的人7402肝癌细胞的杀伤活性明显高于亲本7402细胞组(P<0.05)。说明反义IGF-I基因转移至该肝癌细胞,可提高肿瘤的MHC Ⅰ类和Ⅱ类分子的表达,显示肿瘤细胞的免疫原性增强,并可提高LAK细胞对其杀伤的敏感性。

In this research, we apply the antisense strategy to study the function of IGF- I in human hepatoma lines(7402) by Lipofectin mediated gene transfer. The effect of antisense IGF-I on the expression of MHC and the sensitivity of LAK cytotoxicity of tumor cell were studied. The results showed that human hepotoma lines(7402) were transfected with an amplifiable antisense IGF- I gene. The expression antisense IGF-I RNA in the transfected cells after hygromycin resistant selection was confirmed by northern blot analysis. The transfectants expressed higher level of MHC class I and class II molecules. The susceptibility of the transfected cell to LAK cytotoxicity was greater than that of 7402 parent cells(P<0.05). It suggests that transfecting cells can enhance the expression of MHC class I and class II molecules and suceptibility of 7402 cells to the cytotoxicity of LAK cells.