单细胞电泳检测冰冻保存对外周血细胞DNA的损伤

DNA Damage Caused by Cryopreservation of Peripheral Blood Cells Detected by Single Cell GE 1 Assay

用对ＤＮＡ损伤十分敏感的单细胞电泳技术测试冰冻对正常人外周血细胞ＤＮＡ的损伤效应。结果显示－２０℃和－８０℃冰冻后慧星细胞百分率比４℃保存样品明显增多，损伤程度亦加剧。相对而言４℃保存ＤＮＡ较稳定，但随时间的延长ＤＮＡ完整性受到破坏也越严重。

DNA damage is of concern to research in many fields,especially cancer research and toxicology.To evaluate the possible loss of DNA structural integrity during freezing of cells collected over a periol of time,recently developed single cell gel(SCG) assay has been employed to measure the effects of DNA damage in individual peripheral blood cells stored at 4℃,-20℃and -80℃,respectively.The results showed that the basal ratio of comet cells in frozen cells was significantly higher than that of fresh cells.The increase of the frozen time can enhance the effects of DNA damage.The results suggested that evaluation of DNA damage of cells stored by cryopreservation may produce artificially exaggerated levels of damage,which could limit analytical interpretation.