【摘要】 目的 :探讨FasL和B7 1联合基因转移是否具有协同的抗肿瘤效应。方法 :采用重组腺病毒载体将FasL和B7 1基因导入人肺癌细胞A 5 49,G418阳性克隆筛选 ,流式细胞分析 ,RT PCR显示FasL和B7 1的表达 ,并且通过Hoechst3 3 3 42染色和DNA片段分析检测肺癌细胞的凋亡 ;将携带FasL和B7 1基因的肺癌细胞 (命名为A 5 49/FB 11)接种于C5 7BL/ 6小鼠背部皮下 ,观测其致瘤性能 ;A 5 49/FB 11致敏的小鼠对野生型瘤细胞是否具有免疫保护作用 ;用A 5 49和A 5 49/FB 11细胞分别经腹腔免疫小鼠 ,得到腹腔浸润淋巴细胞及致敏脾细胞 ,MTT法检测其体外杀伤实验。结果 :FasL和B7 1基因在肺癌细胞中获得高表达并可诱导肺癌细胞的凋亡 ,双基因转染的肺癌细胞的致瘤性明显下降 ;A 5 49/FB 11诱导的CTL (cyto toxicTlymphocyte)对A 5 49的杀伤活性显著高于野生型A 5 49诱导的CTL对相同靶细胞的杀伤活性 ,P <0 0 5 ;A 5 49/FB 11诱导的CTL对A 5 49/FB 11的杀伤率显著高于对野生型A 5 49的杀伤率 ,P <0 0 5。结论 :FasL促进肺癌细胞凋亡 ,B7 1促进抗肺癌CTL的增殖、活化 ,在效应阶段两基因发挥着重要的协同作用。更多还原

【Abstract】 OBJECTIVE:To study the activation of CTLs against lung cancer cells induced by FasL and B7-1 gene modified tumor cells. And to explore whether co-expression of FasL and B7-1 in A-549 tumor cells could initiate an synergistic antitumor effect.METHODS: FasL and B7-1 gene were transfected into human lung cancer A-549 cells with adenovirus-mediated. The positive clones were selected by G418. The flow cytometry, RT-PCR showed that FasL and B7-1 were highly expressed. FasL+/B7-1+ A-549 (A-549/FB-11) cells were inoculated into the back of C57BL/6 mice subcutaneously and then it decreased their tumorigenicity greatly,P<0.01. The A-549/FB-11 cell sensitized mice obtained the protective immune activity against the rechanllenge of wild type A-549cells,P<0.05. The abdominal infiltrating lymphocytes and sensitizing spleen cells were obtained from the mice who were immunized with A-549/FB-11 or wild type A-549 cells intraperitoneally, and the cytotoxicity of these CTLs against tumor cells was detected by MTT assay.RESULTS: It showed that the cytotoxicity of CTL induced by A-549/FB-11 against A-549 was significantly higher than the cytotoxicity of CTL induced by wild A-549 against the same target cells,P<0.05.CONCLUSIONS: The results suggest that the FasL and B7-1 can effectively promote the activity of CTL against lung cancer cells. And FasL/B7-1 molecules play an important role in CTL cytotoxicity function as well. After introduced into A-549 cells, Ad-B7-1 shows enhanced therapeutic efficiency for A-549 cells when combined with Ad-FasL. [更多还原