~(60)Co照射及低温保存对转基因细胞影响的分析

目的　观察经放射前后的转基因细胞Tca8113/TNF α的TNF α的分泌情况 ,为转基因细胞经致死剂量的放射线灭活作为“瘤苗”应用于临床前TNF α基因的有效表达提供依据。方法　利用基因转染技术 ,用逆转录病毒载体将肿瘤坏死因子基因 (TNF α基因 )转导入人舌癌Tca8113细胞 ,并获得表达 ;在此基础上 ,通过ELISA法分析转基因细胞Tca8113/TNF α在60 Co放射组及未放射组的TNF α分泌量的变化以及经液氮储存 4 8h、一周复苏后的TNF α分泌量的变化。结果　 (1) 60 Co放射组转基因细胞Tca8113/TNF α的TNF α的分泌量 (x±s) (pg/ml/ 10 6细胞 /2 4h)平均高达 (110± 5 6 2 ) ,而未转基因的Tca8113细胞的上清液中未检测到TNF α ,统计学上有明显的差异性 (P <0 0 1) ;(2 )经频率为 4 39 5cGy/min ,总剂量为 10 0 0 0cGy的60 Co放射后TNF α分泌量降低 ,但在 4～ 6d时有一分泌高峰 ;(3)转基因细胞Tca8113/TNF α经60 Co放射后在经 4 8h及一周的液氮内储存后TNF α能够分泌 ,其分泌量的变化趋势同储存前。 4 8h组和一周组之间无明显的统计学差异性。结论　转基因细胞Tca8113/TNF α作为“瘤苗”应用时 ,目的基因的表达可初步评价为有效

THE ANALYSIS OF THE SECRETION OF TNF-αBY TRANSGENIC CELL Tca8113/TNF-α AFTER RADIATED BY ~(60)Co AND KEPT BY LIQUID NITROGEN

Objective To investigate the expression levels of TNF α of transgenic human tongue squamous carcinoma cell line Tca8113/TNF α before and after radiated by 60 Co as tumor vaccine. Methods TNF α gene was transduced into human tongue squamous carcinoma cell line Tca8113 and was expressed stably on the basis of the construction of retroviral LXSN·TNF α. The expression levels of TNF α of Tca8113/TNF α before and after radiated by 60 Co in vitro was tested by means of ELISA techniques. So did the recovered Tca8113/TNF α after kept by the liquid nitrogen for 48 hours and one week. Results The results indicated that (1) the expression level( x ± s )(pg/ml/10 6cells/24hours) of TNF α of Tca8113/TNF α was about 110±5 62pg/ml, but that of the Tca8113 was not detected ( P <0 01); (2) the expression levels of TNF α of Tca8113/TNF α after radiated by 60 Co were not as high as those of Tca8113/TNF α before radiated by 60 Co, but a secreted peak was founded at the forth to the sixth day after radiated by 60 Co; (3) the recovered Tca8113/ TNF α could expressed and have a similar tendency with the Tca8113/TNF α after radiated by 60 Co. Conclusion The initial experiment suggested that the application of gene transduced cell Tca8113/TNF α as tumor vaccine was basically efficient and reliable.