MTT方法测定培养细胞抗药水平的评价

用ＭＴＴ方法测定了多药抗药细胞ＭＣＦ－７Ａｄｒ及其敏感细胞ＭＣＦ－７ＷＴ对阿霉素、长春新碱、秋水仙碱的化学敏感性。ＭＣＦ－７Ａｄｒ与ＭＣＦ－７ＷＴ相比，对三种药物有明显的抗药性。维拉帕米可逆转ＭＣＦ－７Ａｄｒ对阿霉素的抗药性。随选择药物撤除时间的延长，ＭＣＦ－７Ａｄｒ的抗药水平逐渐下降。Ｓｏｕｔｈｅｒｎ杂交显示ＭＣＦ－７Ａｄｒ细胞有典型的ＭＤＲ１基因扩增现象。用ＭＴＴ方法测定Ｓｗｉｓｓ３Ｔ３细胞对阿霉素、长春新碱、秋水仙碱的化学敏感性，同时测定时各亚克隆株间差异较小，而分批测定时，不同批次相差很大。结果说明，ＭＴＴ方法能有效地检测出抗药细胞株的相对抗性；并提示，应在同时用完全相同的条件进行杀伤试验与ＭＴＴ测试，以避免批次间差异。

Evaluation of MTT assay for tests of drug resistance of cultured cells

The chemosensitivity of multidrug resistant cell MCF-7Adr and drug sensitive cell MCF-7WTto doxorubicin,vincristine and colchicine was tested by MTT assay.MCF-7Adr was obviously resistant to these drugs compared to MCF-7WT.Verapamil partially reversed the resistance of MCF-7Adr to doxorubicin.The resistant level of MCF-7Adr to doxorubicin gradually decreased after withdraw of the selected drug.Southern hybridization demonstrated a typical amplification of MDR1 gene in MCF-7Adr cell.The chemosensitivity of Swiss 3T3 cells to doxorubicin,vincristine and colchicine was also tested with MTT assay.When the subclones were tested simultaneously,IC50 S varied small,While IC50 S varied greatly when the subclones were tested sequentially.The results indicate that MTT assay Is able to test the relative drug resistance of multidrug resistant cells,and suggest that cell killing and MTT assay should be done simultaneously to avoid the difference between batches.