应用逆转录病毒载体将IL-2基因导入人红白血病细胞系K562细胞中。转导18天后,细胞DNA周期分析发现空载体转导的细胞K562/neo及含IL-2基因载体转导的细胞k562/IL-2的G0/G1期比例降低,而G2 M期增高。转导30天后K562/neo DNA周期分布恢复至转导前水平,而K562/IL-2细胞G0/G1期比例仍低于未转导细胞,G2 M期仍高于未转导细胞。MTT法检测细胞增殖活性观察到K562/IL-2从培养第4天起增殖活性明显落后于未转导细胞,核分裂指数亦低于水转导细胞。光学显微镜观察见K562/IL-2细胞中出现较多巨大细胞及多核巨细胞,细胞核数目可多达20余个,推测多核巨细胞的形成可能与细胞核反复分裂而胞质不能分裂有关。进一步形态计量学分析证实IL-2基因修饰的K562细胞体积增大,巨大细胞出现率显著高于未转导的K562细胞。结果提示K562/IL-2细胞体积增大与G2 M期细胞比例增高有关,推测IL-2基因修饰可能导致K562细胞周期滞留于G2期。

IL-2 gene was introduced into human erythroleukemic cell line K562 by retroviral vector. After transduction for eighteen days, flow microfluorometric analysis for DNA distribution of both K562/neo and K562/IL-2 cells indicated that transduced cells were accumulated in a state of G2M arrest. Thirty days later, the number of G2 M in K562/neo cells decreased, but proportion of G0/G1 in K562/IL-2 cells was still lower and G2 M was higher than that of nontransduced cells. The proliferative activity assay by MTT method demonstrated that the proliferation of K562/IL-2 was slow following four day culture. The index of mitosis was decreased. The results of light microscopical studies showed many giant and multinucleate giant cells with even more than twenty nuclei in each cell. It was possible that the formation of multinucleate giant cells associated with repeated endomitosis in a single cell. Further analysis of morphometry confirmed that the size of IL-2 gene modified K562 cells was increased. The ratio of giant cells was higher than that of nontransduced K562 cells. We suggested that I1-2 gene transduction might have some regulation effects on proliferative activity of K562 cells. IL-2 gene modified K562 cells might be blocked at a stage of G2.

R730.21