An automated scoring procedure for the micronucleus test by image analysis
An automated scoring procedure for the micronucleus test by image analysis
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DOI：
10.1093/mutage/geh047
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发表时间：
2004-09-01
期刊：
影响因子：
2.7
通讯作者：
Vogel, W
中科院分区：
文献类型：
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作者：
Varga, D;Johannes, T;Vogel, W
人淋巴细胞微核试验(MNT)常被用来评估环境诱变剂所致的染色体损伤，评估诱变剂的效应，或寻找诱变后DNA修复能力下降的原因。我们已经建立了基于计算机图像分析的胞质分裂受阻MNT的自动评分程序(MetasSystems Metafer4版本2.12)。为了评估结果，我们使用计数的重复性，建立了伽玛射线照射的剂量-反应曲线，并使用系统区分乳腺癌患者和对照组的能力作为生物学参考，这是我们以前通过视觉计数观察到的差异。血培养开始时用2Gy射线照射，最后24 h用细胞松弛素B处理，玻片用Giemsa染色进行目测计数，用DAPI进行自动分析。我们的测试样本包括73人(27名乳腺癌患者，26名女性和20名男性对照)。在来自同一培养物的玻片中，视觉计数(对照，平均MN频率313)和自动计数(平均MN频率106)之间的比较显示，自动计数的下降幅度很大。然而，自动计数与视觉计数[样本的变异系数(CV)类似于20%；相同载玻片重复计数的变异系数(CV)类似于5%]一样具有重复性，而且两种计数高度相关。此外，病例和对照之间的区分改善了对来自相同培养物的载玻片的自动计数[视觉优势比(OR)小于或等于4，P=0.009；自动OR&>16，P<；0.0001]，并强烈依赖于所使用的参数集。这一改进在另外21个对照和20个病例(OR=11，P=0.0018)的验证样本中得到证实，作为前瞻性或诊断性测试。
The micronucleus assay (MNT) in human lymphocytes is frequently used to assess chromosomal damage as a consequence of environmental mutagen exposure, to assess the effect of mutagens or to search for reduced DNA repair capacity after a mutagenic challenge. We have established an automated scoring procedure for the cytokinesis blocked MNT based on computerized image analysis (Metasystems Metafer 4 version 2.12). To evaluate the results we used the reproducibility of counts, established a dose-response curve for gamma-irradiation and used the ability of the system to differentiate between breast cancer patients and controls as a biological reference, a difference which we had observed before by visual counting. Blood cultures were irradiated with gamma-rays (2 Gy) at the beginning and treated with cytochalasin B during the last 24 h. The slides were stained with Giemsa for visual counting and with DAPI for automated analysis. Our test sample consisted of 73 persons (27 with breast cancer and 26 female and 20 male controls). A comparison between visual counting (controls, mean MN frequency 313) and automated counting (mean MN frequency 106) in slides from the same culture revealed a large drop for the automated counts. However, the automated counts were as reproducible as the visual counts [coefficient of variation (CV) on the sample similar to20%; CV on repeated counts of the same slides similar to5%] and both counts were highly correlated. Furthermore, the discrimination between cases and controls improved for automated counting of slides from the same cultures [visual odds rato (OR) less than or equal to 4.0, P = 0.009; automated OR > 16, P < 0.0001], with a strong dependence on the set of parameters used. This improvement was confirmed in a validation sample of an additional 21 controls and 20 cases (OR = 11, P = 0.0018) performed as a prospective or diagnostic test.