重组艰难梭菌毒素B对小鼠结肠癌CT26细胞的诱导凋亡作用

本文探讨了重组艰难梭菌毒素B(rTcd B)对小鼠结肠癌CT26细胞的诱导凋亡作用。采用不同浓度rTcd B处理CT26细胞, 通过MTT法检测细胞增殖抑制率; 比色法测定Caspase 3活性; 细胞形态学和流式细胞技术检测细胞凋亡。结果表明, rTcd B显著抑制了CT26细胞的增殖, 并呈时间?剂量依赖性; Caspase 3活性在处理6 h后显著升高, 至18 h达到最大值, 与对照组相比差异显著, 具有统计学意义(P<0.05); 荧光显微镜观察到典型细胞凋亡形态学变化, 细胞膜内侧的磷脂酰丝氨酸(PS)异位到了膜外侧, 细胞膜呈明亮的绿色荧光; 通过流式细胞仪检测结果表明, 细胞凋亡率呈时间?剂量依赖性增加。实验结果表明, 重组艰难梭菌毒素B能够诱导小鼠结肠癌CT26细胞凋亡。

The Apoptosis Induction of CT 26 Cells by Recombinant Clostridium difficile Toxin B

To investigate the induction of apoptosis of mouse colonic adenocarcinoma CT26 cells by recombinant Clostridium difficile toxin B (rTcdB), CT26 cells were exposed to different concentrations of rTcd B. Inhibition of cell proliferation was measured by MTT assay. The activation of Caspase 3 was measured by colorimetric method. Cell morphological analysis and flow cytometry were performed to confirm cell apoptosis. rTcd B inhibited the proliferation of CT26 cells in a time- and dose-dependent manner. Caspase 3 activity in CT26 cells was elevated remarkably after rTcd B exposure for 6 h, 12 h, 18 h or 24 h, as compared with the control group. Morphological changes were observed by fluorescence microscopy. The exposure of rTcd B to CT26 cells induced a time- and dose-dependent apoptotic cell death as determined by flow cytometry analysis. The results showed that recombinant Clostridium difficile toxin B induced apoptosis of CT26 cells.