Price P, McMillan T J
Radiotherapy Research Unit, Institute of Cancer Research, Sutton, Surrey, United Kingdom.
Cancer Res. 1990 Mar 1;50(5):1392-6.
Three human tumor cell lines of widely differing radiosensitivity were used to examine the characteristics of the 3-[4,5-dimethyl(thiazol-2-yl)-3,5-diphery]tetradium bromide (MTT) assay and to select suitable conditions for its use in assessing the response of cells to ionizing radiation. The optimal concentration of MTT and the time of incubation of the cells with MTT were individualized for each cell line. The relationship between absorbance and cell number was not linear over the wide range of cell numbers that were used. A calibration curve of absorbance against cell number for each cell line was therefore used. Using the assay to quantify metabolically viable cells, growth curves of irradiated and unirradiated cells were constructed on days 0-14 after irradiation. Accurate surviving fractions could be calculated only when cells were in exponential growth. Using this modification to its interpretation, the MTT assay was able to provide a reproducible measure of survival, which compared well with clonogenic cell survival measurements. However, the necessity to optimize conditions of the MTT assay for each cell line severely limits its usefulness in determining the radiosensitivity of cells in primary human tumor cultures.
使用三种放射敏感性差异很大的人类肿瘤细胞系来检测3-[4,5-二甲基(噻唑-2-基)-2,5-二苯基]溴化四氮唑蓝(MTT)检测法的特性，并选择合适的条件用于评估细胞对电离辐射的反应。MTT的最佳浓度以及细胞与MTT孵育的时间针对每个细胞系进行了个体化确定。在所使用的广泛细胞数量范围内，吸光度与细胞数量之间的关系并非呈线性。因此，针对每个细胞系构建了吸光度相对于细胞数量的校准曲线。使用该检测法对代谢活性细胞进行定量，在照射后的第0 - 14天绘制了照射和未照射细胞的生长曲线。只有当细胞处于指数生长时，才能准确计算存活分数。通过对其解读进行这种改进，MTT检测法能够提供可重复的存活测量值，与克隆形成细胞存活测量结果相比良好。然而，针对每个细胞系优化MTT检测条件的必要性严重限制了其在确定原代人类肿瘤培养物中细胞放射敏感性方面的用途。
