Frieauff W, Pötter-Locher F, Cordier A, Suter W
Novartis Pharma, Basel, Switzerland.
Mutat Res. 1998 Feb 23;413(1):57-68. doi: 10.1016/s1383-5718(98)00016-3.
The in vitro micronucleus test is a well established test for early screening of new chemical entities in industrial toxicology. For assessing the clastogenic or aneugenic potential of a test compound, micronucleus induction in cells has been shown repeatedly to be a sensitive and specific parameter. As a measure for numerical and structural chromosome aberrations, the in vitro micronucleus test consists of determining the frequency of micronucleated cells in a representative fraction of cells in a culture. So far, manual counting has been the only method for evaluating microscopic V79 Chinese hamster cell preparations. To replace this tedious and time consuming procedure, a fully automatic system for micronucleus scoring in V79 cells by image analysis has been developed and introduced into the routine genotoxicity screening of drug candidates. The comparison of manual and automatic micronucleus analysis showed a high degree of concordance between the results obtained by the two techniques. For concentration series of cyclophosphamide (CP) and ethyl-methanesulphonate (EMS) as test compounds, the frequency of erroneously missed micronuclei through automatic scoring proved to be below 15% in comparison with manual scoring. Generally, false positive micronucleus decisions could be controlled easily by fast and simple relocation of the automatically detected patterns. The possibility to analyze 24 slides within 1 day by fully automatic overnight analysis and the high reproducibility of the results make automatic image processing a powerful tool for the in vitro micronucleus analysis.
体外微核试验是工业毒理学中用于新化学物质早期筛选的一种成熟试验。对于评估受试化合物的致断裂或致非整倍体潜力，细胞中的微核诱导已被反复证明是一个敏感且特异的参数。作为数值和结构染色体畸变的一种衡量方法，体外微核试验包括测定培养物中代表性细胞部分的微核化细胞频率。到目前为止，人工计数一直是评估显微镜下V79中国仓鼠细胞制剂的唯一方法。为取代这一繁琐且耗时的程序，已开发出一种通过图像分析对V79细胞进行微核评分的全自动系统，并将其引入药物候选物的常规遗传毒性筛选中。人工和自动微核分析的比较表明，两种技术所得结果高度一致。对于作为受试化合物的环磷酰胺（CP）和甲基磺酸乙酯（EMS）的浓度系列，与人工评分相比，自动评分错误遗漏微核的频率被证明低于15%。一般来说，通过快速简单地重新定位自动检测到的模式，可轻松控制假阳性微核判定。通过全自动过夜分析在1天内分析24张玻片的可能性以及结果的高重现性，使得自动图像处理成为体外微核分析的强大工具。
