اثرات سيتوتوكسيك وروتوكسين تيپ 1 بر روي رده هاي سلولي VERO و MCF-7

Comparative study of cytotoxic effect of verotoxin l on Vero and MCF-7 cells

Introduction: Verotoxins are subunit toxins, that involve in pathogenesis of Enterohemorrhagic Escherichia coli. Early studies of cytotoxicity on tumor cells indicate that verotoxin) is effective in in vitro and laboratory animals. Because of specific receptors on studied tumor cells, verotoxin) exerts selective cytotoxicity. The purpose of this study was to compare the cytotoxicity of verotoxin] on vero and MCF-7 cell lines. Methods: Toxin production in five verotoxigenic straines was screened by verotoxin producing Escherichia coli-reverse passive latex agglutination test (VTEC-RPLA kit, Oxoid, Co, Ltd) and after confirming verotoxin I production from one of them, toxin purified by affinity chromatography. Then Vero and MCF-7 cells treated with serial dilutions of toxin, and viability and fragmentation of genome were studied . Results: Our results indicated that MCF-7 cells was also susceptibile. The Lethal Dose 50% (LD 50%) for the treated cells was about 50 nanograms of toxin per milliliter. Evidences of apoptosis in the cells were studied by the fragmentation of DNA. Conclusion: Our results are in accordance with previous studies about cytotoxicity of verotoxin) against human tumor cells and specially breast cancer lines. It indicates that verotoxin/ can he used as a potential selective cytotoxic factor against wide variety of human tumors.