卷烟烟气致人淋巴细胞细胞毒性和遗传毒性的体外试验

目的 用不同体外试验评价卷烟烟气粒相物提取液(CSCs)致人外周血淋巴细胞的细胞毒性和遗传毒性.方法 分别以25、50、75、100和125 ug/ml的CSCs在加或不加肝脏微粒体酶(S9)系统下作用于人外周血淋巴细胞3 h,然后用CCK-8试验检测细胞毒性,用彗星试验检测DNA损伤,用hprt和TCR基因突变试验检测体细胞突变;以75ug/ml的CSCs作用于人外周血淋巴细胞3 h,分别给予30、60、90、120和240 min的修复时间,然后用彗星试验评价淋巴细胞的DNA修复情况.结果 细胞活性随剂量增加明显降低,100、125 ug/ml CSCs加S9组细胞活性明显高于不加S9组,差异有统计学意义(P<0.05,P<0.01);随CSCs暴露剂量增加,DNA损伤明显增加,并明显高于对照组,差异有统计学意义(P<0.01);各剂量加S9组DNA损伤明显低于不加S9组,差异有统计学意义(P<0.05,P<0.01).各剂量组TCR基因突变率明显高于对照组,差异有统计学意义(P<0.05,P<0.01).中高剂量组hprt基因突变率明显高于对照,差异有统计学意义(P<0.01),中、高剂量加S9与不加S9两组间TCR和hprt基因突变率均存在明显差异,差异有统计学意义(P<0.05,P<0.01).加与不加S9两组DNA损伤均可基本修复至正常水平,但两者修复速度存在差异.结论 CSCs可在体外诱发人外周血淋巴细胞的细胞和遗传损伤,但S9可降低CSCs毒性的效应,并可影响人淋巴细胞DNA损伤的修复速率.

Cyto-genotoxicity induced by cigarette smoke condensates in human peripheral blood lymphocytes in vitro

Objective To investigate the cyto-genotoxicity of cigarette smoke condensates (CSCs) in human peripheral blood lymphocytes with different assays in vitro. Methods Human lymphocytes were ex-posed to particle matter of cigarette smoke combined with or without S9 mixtures at doses of 25,50,75,100 and 125 ug/ml for 3 h. The cytotoxicity induced by CSCs was detected by CCK-8 assay. The DNA damage, DNA repair (repair time: 30, 60, 90, 120 and 240 min, respectively) and the somatic cell mutations induced by 75 ug/ml CSCs were measured by comet assay, hprt gene and TCR gene mutation tests, respectively. Results CCK-8 assay indicated that the cell viability decreased with CSCs doses. At the doses of 100,125 ug/ml, the cell viability of CSCs +S9 group was significantly higher than that of CSCs -S9 group(P<0.05,P< 0.01). In comet assay, DNA damage significantly increased in a dose-dependent manner, as compared with controls (P<0.01). Moreover, there was significant difference between -S9 group and +S9 group (P<0.05, P< 0.01). The Mf-TCR at each dose group was significantly higher than that of controls (P<0.05 ,P<0.01). The Mf-hprt at high-dose groups were significantly higher than that of controls (P<0.01), and significant difference of Mf-TCR and Mf-hprt at high doses of CSCs between -S9 group and +S9 group (P<0.05,P<0.01). The DNA damage induced by CSCs+S9 or CSCs-S9 could be repaired, but DNA repair speed was different between -S9 group and +S9 group (P<0.05, P<0.01). Conclusion CSCs may induce cyto-genotoxicity in human periph-eral blood lymphocytes in vitro, but S9 mix could reduce the toxicity of CSCs and impact DNA repair speed.