[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.


CONCLUSIONS
These five strains of Acanthamoeba exhibit cytotoxic effects of varying degrees on HeLa cells, inducing apoptosis.
Qian
M
M
Department of Biology, East China Normal University, Shanghai 200062.
Zhang
X H
XH
Mei
B
B
Zhang
P
P
Yan
Z
Z
Yu
M
M
D000048:Acanthamoeba / Q000472:pathogenicity*; D000818:Animals; D017209:Apoptosis; D006367:HeLa Cells / Q000469:parasitology; D006801:Humans