Chang W P, Little J B
Laboratory of Radiobiology, Harvard School of Public Health, Boston, Massachusetts 02115.
Int J Radiat Biol. 1991 Sep;60(3):483-96. doi: 10.1080/09553009114552331.
The cytotoxic effects of X-irradiation may be delayed for many generations of replication in mammalian cells. In addition to a reduced cloning efficiency, progeny of surviving Chinese hamster ovary (CHO) cells isolated after 12-34 population doublings postirradiation showed a variety of abnormalities including lower attachment ability to culture dishes and slower cell cycle progression. When these progeny were seeded as single cells 12-23 generations after irradiation, they formed a higher fraction of abortive colonies and of non-homogeneous colonies containing giant cells. All of these characteristics were evident whether progeny cells were subcultured by trypsinization or by mitotic selection. These results suggest that residual damage may be carried by surviving progeny of irradiated cells over many mitotic cycles; this damage is eventually expressed in terms of pleomorphic changes leading to delayed reproductive failure.
X射线辐射的细胞毒性作用可能在哺乳动物细胞的多代复制过程中延迟出现。除了克隆效率降低外，在辐射后经过12 - 34次群体倍增分离出的存活中国仓鼠卵巢（CHO）细胞的子代，表现出多种异常，包括对培养皿的附着能力降低以及细胞周期进程减缓。当这些子代在辐射后12 - 23代作为单细胞接种时，它们形成的流产集落和含有巨细胞的非均匀集落比例更高。无论子代细胞是通过胰蛋白酶消化还是有丝分裂选择进行传代培养，所有这些特征都很明显。这些结果表明，辐射后存活的子代细胞可能在多个有丝分裂周期中携带残留损伤；这种损伤最终表现为导致延迟生殖失败的多形性变化。
