大肠杆菌致U937细胞凋亡的研究

Effect of E.coli on cell apoptosis of U937

目的探讨大肠杆菌感染对人U937细胞凋亡的诱导作用。方法以细胞形态学观察及AnnexinV/PI双染流式细胞仪检测分析大肠杆菌感染U937细胞后,不同作用时间U937细胞的凋亡情况。结果Hoechst33258染色荧光显微镜下观察:大肠杆菌感染20min及30min后偶见细胞凋亡,感染60min及90min时可见许多细胞有典型的凋亡形态学改变,并可见凋亡小体;AnnexinV/PI双染可见U937细胞凋亡百分率随大肠杆菌感染时间延长而增高。感染60min及90min时,细胞凋亡率与其它组相比明显增高,差异有显著性(P<0.001)。结论大肠杆菌以时间依赖方式诱导人类U937细胞凋亡。

[Objective] To study the time-dependent manner of U937 apoptosis induced by E.coli. [Methods] U937 apoptosis was detected with Annexin V/PI assay and morphological detectionat different time after E.coli infecting U937. [Results] Morphologic observation showed that U937 cells in the 60 min and 90 min groups underwent karyopykosis,condensation,swelling and apoptotic bodies were observed. In the 20 min and 30 min groups, very few apoptotic cells were observed. Annexin V/PI assay showed that the percentage of apoptotic cells was raised with the increasing of time. the infection group at 60 min and 90 min can induce significantly U937 apoptosis than in the other groups （P 〈0.001）. [Conclusion] E.coli induces U937 apoptosis in time-dependent manner.