在诱变试验中广泛应用人羊膜FL细胞, 中国仓鼠CHL和V79细胞, 但由于它们不能表达内源性细胞色素P450(CYP)活化前致突变物, 而严重限制了它们的使用. 本工作构建了携有编码CYP2B6单胺氧化酶的cDNA重组表达体并分别导入上述三种细胞中表达, 经G418抗性筛选, 建立了FL-2B6, CHL-2B6和V79-2B6三种转基因细胞系, 用Northern印迹杂交证明它们都有CYP2B6的表达. 在CHL-2B6细胞中还测得较高水平的7-乙氧基-4-三氟甲基香豆素去乙基酶活性, 它对前致突变物甲基亚硝胺吡啶酮的致微核形成作用有很高敏感性, 并呈剂量效应关系, 但其母系细胞皆为阴性.

Human FL cell line, Chinese hamster CHL and V79 cell lines are widely used for mutagenicity testing. However, they can not express cytochrome P-450(CYP), a necessary enzyme for the oxidation of xenobiotics and activation of promutagens/procarcinogens and thus their applications are limited. A full-length cDNA clone encoding the monooxygenase CYP2B6 was constructed and introduced into FL, CHL and V79 cell lines. The new cell lines (FL-2B6, CHL-2B6 and V79-2B6) had been established after G418 selection. Northern blotting showed that all of them expressed CYP2B6 gene. 7-Ethoxy-4-trifluoromethylcoumarin O-deethylation(EFCOD) activity and the bioactivation capacity for nitrosamine promutagen 4-methylnitrosamino- 1-(3-pyridyl)-1-butanone (NNK) were determined. In postmitochondrial supernatant and microsome from the CHL-2B6 cell, the EFCOD activity was 0.84±0.17 and 20.0±2.4 pmol·min^-1·mg^-1 protein respectively, whereas it could not be detected in the parent cell line. And, the CHL-2B6 cell line reproducibly displayed high sensitivity dose-dependently to NNK in inducing micronuclei, while its parent cell line could not.