TRANSFECTION OF CDNAS FOR DRUG METABOLISM INTO MAMMALIAN CELLS

突变用哺乳动物细胞的代谢能力， 通过感染细胞， 含有编码药物代谢酶的cDNA的逆转录病毒载体。 P450的IIA 3、IIB 1和IVB 1以及黄素单加氧酶的cDNA具有 插入到载体中，并感染到C3H 1OT中， 细胞通过Western分析，所有p450和黄素单加氧酶都是 在1OT和二分之一细胞中表达。此外，含有IIB1的细胞 对二甲基亚硝胺的细胞毒性作用的敏感性增加 和乙酰氨基芴，并且含有IVB1的细胞显示出增加的细胞毒性 对氨基芴的影响。香豆素检测细胞色素P450 IIA 3 羟化酶活性，并应激活致癌物质，二甲基-和 二乙基亚硝胺这些研究仍在继续， 并使细胞对更广泛的遗传毒性产生反应， 环境化学物质和模拟致癌物激活，因为它发生 in vivo.

The metabolism capability of mammalian cells used in mutation and transformation assays is being increased by infecting the cells with retroviral vectors containing cDNAs coding for drug metabolizing enzymes. The cDNAs for P450s IIA3, IIB1, and IVB1, and a flavin monooxygenase have been inserted into the vectors and infected into C3H 1OT and one-half cells. By Western analysis, all p450s and the flavin monooxygenase are expressed in the 1OT and one-half cells. Furthermore, cells containing IIB1 have increased sensitivity to the cytoxic effects of dimethylnitrosamine and acetylaminofluorene, and cells containing IVB1 show increased cytotoxic effects to aminofluorene. Cytochrome P450 IIA3 is detected by coumarin hydroxylase activity and should activate the carcinogens, dimethyl- and diethylnitrosamine. The studies are continuing to improve enzyme expression and to make the cells responsive to the genetic toxicity of a wider variety of environmental chemicals and to mimic carcinogen activation as it occurs in vivo.