电离辐射对Jurkat T细胞凋亡与坏死的影响

目的：研究电离辐射诱导Jurkat T细胞凋亡与细胞坏死的变化规律，探讨电离辐射作用后细胞的死亡模式与机理。方法：采用Annexin V-EGFP和PI 双染、流式细胞术(FCM)检测不同剂量（0.075、0.500、1.000、2.000、4.000和6.000 Gy）X射线照射后Jurkat T细胞凋亡与细胞坏死的时间-效应关系和剂量-效应关系。结果：时间-效应关系，2.000 Gy X射线照射后，与假照组比较，Jurkat细胞凋亡百分率在照射后18 h显著增加，至24 h始终维持在较高水平（P＜0.001）；细胞坏死百分率于照射后4 h显著增加，12 h 达峰值，至48 h始终维持在较高水平（P＜0.001）。剂量-效应关系，0.075Gy X射线照射后18 h，Jurkat T细胞凋亡百分率和细胞坏死百分率与假照组相比较未见明显变化（P＞0.05）。2.000~6.000 Gy较大剂量X射线照射后18 h，细胞凋亡百分率和细胞坏死百分率与假照组比较均呈剂量依赖性增加（P＜0.001）。结论：2.000 Gy以上剂量X射线可以诱导Jurkat T细胞发生凋亡和坏死，细胞坏死比细胞凋亡出现时间更早，持续时间更长。

Effect of ionizing radiation on apoptosis and necrosis of Jurkat T cells

Objective To study the effect of ionizing radiation on apoptosis and necrosis of Jurkat T cells,and investigate the model and mechanism of cell death after ionizing radiation.Methods The time-and does-effects on apoptosis and necrosis of Jurkat T cells after X-irradiation with different doses(0.075,0.500,1.000,2.000,4.000 and 6.000 Gy)were detected by using Annexin-V/PI double staining by flow cytometry.Results For the time-effect,the apoptotic percentage of Jurkat cells increased significantly 18 h after irradiated with 2.000 Gy X-rays and kept higher level to 24 h compared with sham-irradiation group(P<0.001).The percentage of necrosis increased strikingly 4 h after irradiation,reached the peak value at 12 h and kept higher level to 48 h(P<0.001).For the does-effect,the percentages of apoptosis and necrosis of Jurkat cells didn't change markedly 18 h after irradiated with 0.075 Gy X-rays compared with sham-irradiation group.The percentages of the apoptosis and necrosis increased in a dose-dependent manner 18 h after irradiated with the higher 2.000-6.000 Gy X-rays compared with sham-irradiation group(P<0.001).Conclusion Apoptosis and necrosis of Jurkat cells may be induced by X-irradiation with the dose of above 2.000 Gy.The cell death occurs earlier and persists longer than apoptosis.