Kinetics of CHO A L mutant expression after treatment with gamma radiation, EMS, and asbestos.
Kinetics of CHO A L mutant expression after treatment with gamma radiation, EMS, and asbestos.
复制标题
伽马辐射、EMS 和石棉处理后 CHO A L 突变体表达的动力学。
DOI：
10.1002/cyto.a.20708
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发表时间：
2009
期刊：
影响因子：
--
通讯作者：
Fox,MichaelH
中科院分区：
文献类型：
--
作者：
Keysar,StephenB;Fox,MichaelH
流式细胞术突变试验（FCMA）使用杂交CHO AL细胞，通过不存在与CD 59表面抗原结合的荧光染料偶联抗体来测量位于人11号染色体上的cd 59基因突变。突变体表达在6和12天之间达到峰值，然后下降到稳定的平台，而不是通过克隆形成测定获得的恒定突变体分数。为了评估这种可变的突变体表达时间，用辐射、EMS或石棉处理细胞，并在导致突变体表达峰值的时间测量细胞增殖和存活。潜在的倍增时间（Tpot）值增加了至少75%，每种药物治疗后3小时，但仅3天后恢复到对照水平。存活率在一周内恢复到对照的90%，接近所有三种试剂的峰值表达日。在表达高峰日分选的CD 59 −细胞的存活率大约是CD 59+细胞的一半。经EMS处理的克隆CD 59 −细胞的倍增时间为16.7 h，而CD 59+细胞的倍增时间为14.1 h。随着时间的推移，三重突变体（CD 59 −/CD 44 −/CD 90 −）优先从人群中消失，而CD 59 −/CD 90 −突变体的比例增加。总之，突变体表达的高峰日仅发生在细胞从诱变剂的毒性作用中恢复时。最初定量为突变体的一部分细胞由于致死性缺失和较慢的生长而随着时间的推移而丢失。© 2009国际细胞计数促进学会
The flow cytometry mutation assay (FCMA) uses hybrid CHO ALcells to measure mutations of thecd59gene located on human chromosome 11 by the absence of fluorochrome‐conjugated antibody binding to the CD59 surface antigen. Mutant expression peaks between 6 and 12 days, then decreases to a stable plateau, instead of a constant mutant fraction obtained by clonogenic assays. To evaluate this variable mutant expression time, cells were treated with radiation, EMS or asbestos and cell proliferation and survival were measured at times leading up to peak mutant expression. Potential doubling time (Tpot) values increased by at least 75% for each agent by 3 h after treatment but returned to control levels after only 3 days. Survival returned to 90% of control within a week, close to the peak expression day for all three agents. The survival of CD59−cells sorted on the peak day of expression was roughly half that of CD59+cells. Cloned EMS‐treated CD59−cells had a doubling time of 16.7 vs. 14.1 h for CD59+cells. Triple mutants (CD59−/CD44−/CD90−) were preferentially lost from the population over time, while the proportion of CD59−/CD90−mutants increased. In conclusion, the peak day of mutant expression occurs only when cells recover from the toxic effects of the mutagen. A fraction of cells originally quantified as mutants are lost over time due to lethal deletions and slower growth. © 2009 International Society for Advancement of Cytometry