沙门菌对小鼠胃癌细胞增殖及β-防御素-2表达的影响

Effect of Salmonella on proliferation of mouse gastric carcinoma MFC cells and expression of mouse β-defensin-2

目的探讨沙门菌对小鼠胃癌细胞MFC增殖及β-防御素-2(mouseβ-defensin,m BD-2)表达的影响。方法将不同浓度(10、10~2、10~3和10~4个/ml)沙门菌分别作用MFC细胞不同时间(12、24和48 h)后,MTT法检测沙门菌对细胞抑制的最佳浓度及时间;TUNEL法检测不同浓度(10、10~2、10~3和10~4个/ml)沙门菌作用MFC细胞不同时间(12、24和48 h)对细胞凋亡的影响;将不同浓度(10、10~2、10~3和10~4个/ml)沙门菌作用MFC细胞4、8和12 h,定量PCR及Western blot法检测m BD-2 m RNA及蛋白水平。结果浓度103个/ml沙门菌作用24 h对MFC细胞的抑制作用明显,细胞凋亡也明显;沙门菌作用MFC细胞8 h时,m BD-2的表达量无论在蛋白还是m RNA水平均较高。结论m BD-2的表达在浓度103个/ml沙门菌作用8 h后达到最高,为进一步研究m BD-2的产生机制奠定了基础。

Objective To investigate the effect of Salmonella on proliferation of mosue gastric carcinoma MFC cells and expression of mouse β-defensin （mBD）-2. Methods The proliferation level of MFC cells treated with Salmonella at various concentrations （10, 102, 103 and 104 bacteria/ml） for various （12, 24 and 48） hours were determined by MTI＇ assay, based on which the concentration and time of Salmonella for inhibition of MFC cell proliferation were optimized. The apoptosis of MFC cells treated with Salmonella for various （12, 24 and 48 ） hours was determined by TUNEL method. MFC cells were treated with Salmonella at concentrations of 10, 102, 103 and 104 bacteria/ml for 4, 8 and 12 h separately, in which the expression levels of mBD-2 mRNA and protein were determined by PCR and Western blot respectively. Results The proliferation of MFC cells was inhibited significantly after treatment with Salmonella at a concentration of 103 bacteria / ml for 24 h, while obvious apoptosis was observed. Both the expression levels of mBD-2 mRNA and protein reached the maximum in MFC cells after treatment with Sahnonella for 8 h. Conlusion The expression level of mBD-2 reached the maximum in MFC cells after treatment with Salmonella at a concentration of 103 bacteria/ml for 8 h, which laid a foundation of further study on mechanism of production of mBD-2.