在体外微核试验中测试了以下参考基因毒性剂,在诺华,巴塞尔,瑞士。丝裂霉素C,5-氟尿嘧啶,在人淋巴母细胞细胞系TK6中测试了秋水仙碱和依托泊苷,有或没有胞质分裂阻滞(存在细胞松弛素B)。这样做是为了支持经合组织体外哺乳动物细胞微核测试(MNvit)测试指南草案中建议的毒性措施,并且是国际合作工作的一部分。作为毒性措施,检测细胞停滞和细胞死亡,相对细胞计数(RCC),细胞计数(RICC)的相对增加,和相对人口倍增(RPD)用于在没有胞质分裂阻滞的治疗,和复制指数(RI)或胞质分裂阻滞存在下的胞质分裂阻滞增殖。在有和没有胞质分裂阻滞的测定中,所有四种参比试剂均为阳性,其浓度为约50%毒性或更低,如通过所有使用的毒性测量所评估的。因此,这项工作的结果支持使用相对种群加倍和细胞计数的相对增加,以及相对细胞计数,作为非胞质分裂阻断的体外微核试验的适当毒性措施。
The following reference genotoxic agents were tested in the in vitro micronucleus test, at Novartis, Basel, Switzerland. Mitomycin C, 5-fluoruracil, colchicine and etoposide were tested in the human lymphoblastoid cell line TK6, with and without cytokinesis block (in the presence of cytochalasin B). This was done in support of the toxicity measures recommended in the draft OECD Test
Guideline on In Vitro Mammalian Cell Micronucleus Test (MNvit) and was part of an international collaborative work. As toxicity measures, detecting cytostasis and cell death, relative cell counts (RCC), relative increase in cell counts (RICC), and relative population doubling (RPD) were used for treatments in the absence of cytokinesis block, and replication index (RI) or cytokinesis-blocked proliferation in the presence of cytokinesis block. All four reference agents were positive in the assay with and without cytokinesis block at concentrations giving approximately 50% toxicity or less as assessed by all of the toxicity measures used. Accordingly, the results of this work support the use of relative population doubling and relative increase in cell counts, as well as relative cell counts, as appropriate measures of toxicity for the non-cytokinesis-blocked in vitro micronucleus assay.