SEA诱导人PBMC对结肠癌Caco-2细胞的杀伤效果观察

目的通过蛋白注入和基因转染两种形式，观察金黄色葡萄球菌肠毒素A（SEA）诱导人外周血单核细胞（PBMC）对结肠癌Caco-2细胞的杀伤效果。方法密度梯度离心法分离PBMC，用不同浓度SEA诱导；MTT法测定PBMC对Caco-2细胞的杀伤率；用阳离子脂质体法将重组质粒pEGFP-N1-SEA转染至Caco-2细胞，检测PB—MC对该细胞的杀伤率。结果在一定范围内，随着SEA浓度的升高，PBMC对Caco-2细胞的杀伤率显著上升，在36h、高效靶比、高SEA浓度的情况下，杀伤率可达57．23％；将pEGFP-N1-SEA转染至Caco-2中，转染效率达55％，同时能显著提高PBMC的杀伤率，转染60h后杀伤率可达54．62％。结论通过蛋白注入和基因转染两种形式，SEA均能诱导并增强PBMC对Caco-2细胞的杀伤效果。

Observation of the anti-tumor activity of peripheral blood mononuclear cell induced with SEA on colon cancer cell line Caco-2

Objective To observe the anti-tumor activity of peripheral blood mononuclear cell （PBMC） induced with staphylococcus enterotoxin A（SEA） via two different means of protein injection and gene transfection. Methods Separated PBMC by density gradient centrifugation, induced PBMC with the different concentrations of SEA, and determined the kill rate of PBMC on Caco-2 by MTT. Transfected the recombination plasmid pEGFP-N1-SEA into Caco-2 by cationic liposome method, and then determined the kill rate of PBMC. Results By increasing the concentration of SEA, the kill rate of PBMC on Caco-2 was remarkably enhanced in a certain range, and 36 h later the kill rate was 57.23% at highest effector-target ratio and the highest concertration of SEA. Transfected the pEGFP-N1-SEA into Caco-2, and transfection efficiency was about 55%. The kill rate of PBMC was remarkably enhanced, and it was 54.62% at 60 h after transfection. Conclusion SEA can induce and increase the tumor-cytotoxicity effect of PBMC by two different means of protein injection and gene transfection.