浓缩铀诱发免疫细胞凋亡的形态观察及IL-2和IL-6的防护作用

对浓缩铀２３５Ｕ内照射人淋巴细胞白血病细胞株Ｍｏｌｔ４细胞和巨噬细胞株Ａｎａ１细胞诱发的细胞凋亡及细胞因子的防护作用进行了研究。实验中估算了２３５Ｕ在不同阶段培养细胞中的辐射累积吸收剂量。通过荧光显微镜形态观察，发现免疫细胞在受２３５Ｕ辐照后，可诱发明显的以核断裂和核固缩为特征的细胞凋亡。微观放射自显影研究显示，２３５Ｕ可迅速被免疫细胞吞噬，在细胞内以吞噬小泡的形式均匀地弥散于胞浆和胞核内。研究发现，ＩＬ２和ＩＬ６这两个细胞因子对由２３５Ｕ诱发的免疫细胞ＤＮＡ链断裂具有显著的防护作用。研究结果对于临床上寻找提高内照射放射治疗病例的免疫功能措施，具有一定的价值。

MORPHOLOGICAL STUDIES ON APOPTOSIS IN IMMUNE CELLS INDUCED BY 235 U AND THE RADIOPROTECTION OF IL 2 AND IL 6

Cell apoptosis in human acute lymphoblastic cell line Molt 4 and macrophage cell line Ana 1 was induced by 235 U. The cumulative radiation absorption doses of 235 U in cultured cells through different periods were estimated. The morphological changes in Molt 4 and Ana 1 cells were observed by fluorescence microscopy. We found that Molt 4 and Ana 1 cells, internally irradiated by 235 U, displayed a significant nuclear fragmentation and a marked pyknosis. The microautoradiographic study showed that at first 235 U was phagocytized by Molt 4 and Ana 1 cells, and then 235 U was homogeneously distributed through the cells. The finding indicated that 235 U can significantly increase the DNA fragmentation and apoptotic bodies formation in the immune cells, and this effect could be inhibited by IL 2 and IL 6. So both IL 2 and IL 6 showed radioprotective effect on Molt 4 and Ana 1 cells internally irradiated by 235 U.