人MutS同源蛋白2(hMSH2)过表达的肺癌细胞模型的构建

摘要

Objective To construct human lung cancer cell model with human MutS homologous protein 2 (hMSH2) overexpression for exploring the effect of hMSH2 molecule in the cytotoxicity of γδ T cell against lung cancer cells.Methods hMSH2 coding sequence was cloned by PCR for construction of recombinant vector which over expressed hMSH2-EGFP fusion protein using homologous recombination.The recombinant vector was transfected to lung cancer cell line NCI-H520 to construct human lung cancer cell model overexpressing hMSH2 molecule.The expression of hMSH2 molecule in NCI-H520 was detected by Western blot.The expression of hMSH2 on the cell membrane was measured by flow cytometry.Cytotoxicity of expanded γδ T cells from peripheral blood mononuclear cells against NCI-H520 cells was detected by LDH release assay in vitro.Results hMSH2 coding sequence (2805 bp) was cloned and the result of restriction endonuclease digestion of Fugw-hMSH2 recombinant vector was accordance with the anticipated objective strip size.Exogenous hMSH2-EGFP fusion protein was expressed in NCIH520 cells.The level of hMSH2 molecule on the surface of NCI-H520 cells with overexpression of hMSH2 was significantly increased (P＜0.001).Cytotoxicity of γδ T cells against NCI-H520 cells with overexpression of hMSH2 was significantly increased compared to the wild type NCI-H520 cells (P＜0.05).Conclusions Lung cancer cell model that overexpresses hMSH2 molecule is successfully constructed,hMSH2 molecule on the cell membrane is increased and the cytotoxicity of γδ T cells against lung cancer cells is enhanced.%目的 构建人MutS同源蛋白2(hMSH2)过表达的肺癌细胞模型,探究hMSH2分子介导γδ T细胞杀伤肺癌细胞的效应.方法 PCR扩增hMSH2编码序列,同源重组法构建hMSH2-EGFP融合蛋白过表达载体;转染肺癌细胞系NCI-H520细胞以构建hMSH2分子过表达的NCI-H520细胞模型;Western blot检测细胞中hMSH2分子表达,流式细胞计量术检测细胞膜上hMSH2分子表达,体外扩增人外周血单个核细胞中的γδ T细胞,乳酸脱氢酶释放法检测γδ T细胞对过表达hMSH2的NCI-H520细胞的杀伤效率.结果 获得hMSH2编码序列(2 805 bp),构建Fugw-hMSH2重组载体,酶切鉴定结果与预期目的条带大小相符;hMSH2-EGFP融合蛋白在NCI-H520细胞中得到表达,过表达hMSH2的NCI-H520细胞表面的hMSH2分子水平显著升高(P＜0.001);yδ T细胞对过表达hMSH2的NCI-H520细胞的杀伤效率较野生型NCI-H520细胞显著升高(P＜0.05).结论 成功构建hMSH2分子过表达的肺癌细胞模型;细胞膜上表达水平上调的hMSH2分子增强了γδ T细胞对肺癌细胞的细胞毒作用.