外周血淋巴细胞凋亡依赖于细胞周期运行

目的以培养的人类正常外周血淋巴细胞（peripheral blood lymphocytes，PBLs）为模型，模拟细胞周期运行的不同状态，研究细胞凋亡与细胞周期运行的关系。方法将PHA及咖啡因处理前后的PBLs，分别用喜树碱（CPT）、X-射线、抗Fas抗体和肿瘤坏死因子TNF-α诱导，流式细胞术方法对细胞凋亡进行定量检测。结果PBLs经PHA刺激后进入细胞周期并发生凋亡，在凋亡因子打击作用下凋亡明显增加，用咖啡因废除细胞周期检测点后对凋亡打击敏感性降低。未经PHA刺激的PBLs对凋亡打击无应答。结论细胞进入细胞周期总是伴随细胞凋亡的发生，细胞不进入周期，则不会发生凋亡，细胞周期不停止，也不会凋亡。细胞周期检测点是联结细胞周期和细胞凋亡的重要位点。

APOPTOSIS OF PBLs DEPENDS ON CELL CYCLE PROGRESSION

Objective To investigate the relationship between apoptosis and cell cycle progression in cultured normal human peripheral blood lymphocytes （PBLs） at different stages of cell cycle progression. Methods Apoptosis was induced by camptothecin, X-ray, anti-Fas antibody and TNF-α, respectively, in PBLs treated with PHA or caffeine, and then examined quantitatively by flow cytomety. Results PHA-stimulated PBLs began the cell cycle and apoptosis, and additional cells were recruited following additional apoptotic insults. The proliferating PBLs became insensitive to the insults after the cell cycle checkpoint was abolished by caffeine. Unstimulated PBLs remained unresponsive to apoptosis. Conclusion Apoptosis always accompanies cell cycle progression. Without the beginning or the end of the cell cycle, there is no apoptosis. Cell cycle checkpoint offers the platform for both cell cycle and apoptosis.