棘阿米巴滋养体对HeLa细胞的细胞毒性作用

目的　探讨处于不同分类地位的 5株棘阿米巴滋养体对人HeLa细胞的细胞毒性作用。方法　将 5株不同虫株的棘阿米巴滋养体分别与体外培养的人HeLa细胞混合 ,观察其对肿瘤细胞的影响。并采用光镜确定肿瘤细胞的形态学变化特征 ,采用MTT(四甲基偶氮唑盐 )法检测并比较这 5种棘阿米巴对肿瘤细胞作用的差异。结果　MTT法显示 ,当棘阿米巴滋养体与HeLa细胞以 1∶1比例混合时 ,对肿瘤细胞表现出较强的细胞毒性作用。该作用不仅具时间依赖性 ,且因棘阿米巴的虫株不同而异。光镜下染色标本显示 ,经 5株棘阿米巴滋养体作用后的肿瘤细胞均出现了核染色质边集浓缩和胞膜出空泡等细胞凋亡的形态学特征。结论　这 5株棘阿米巴滋养体对HeLa细胞均有不同程度的细胞毒性作用 ,并诱导肿瘤细胞发生细胞凋亡。

Cytotoxic Effect of Acanthamoeba Trophozoite on Hela Cells

OBJECTIVE: To investigate the cytotoxic effect(CTE) on human cervix cancer HeLa cells induced by five strains of pathogenic free-living Acanthamoeba. METHODS: The cytotoxic effect of five isolates of Acanthamoeba on HeLa cells was investigated by light microscopy and MTT method. RESULTS: The photomicrographs of HeLa cells showed a sequence of cardinal morphological features of apoptosis when HeLa cells were exposed to Acanthamoeba in a time-dependent manner at a ratio of 1:1 for 12 h. MTT method showed more than 50% of tumor cells underwent cytolysis following exposure to A. lugdunensis trophozoites, and only 18% of cells treated with A. polyphaga underwent CTE. The CTE produced by A. lugdunensis and A. quina trophozoites was more rapid than the others, beginning as early as 6 h after coincubation and resulting in cytolysis by 72 h. CONCLUSION: These five strains of Acanthamoeba exhibit cytotoxic effects of varying degrees on HeLa cells, inducing apoptosis.