[The bystander effect of HSV-tk/GCV system on human cervical carcinoma cell line ME180].

OBJECTIVE: To investigate the bystander effect of HSV-tk/GCV system-retroviral vector mediated on human cervical carcinoma cell line ME180 (ME).

METHODS: By the use of lipofectin and polybrene transfection techniques, recombinant retroviral vector-plxsn-HSV-tk was tansduced into packing cell line PA317 and the obtained recombinant retrovirus was applied to infect ME cells and establish transfection cell line. The effect of GCV on survival rate and bystander effect of ME and ME/TK cells was observed by cell culture and MTT test.

RESULTS: Transduction of TK gene into PA317 and ME cell lines was successful and validated by viral titer, electron microscope and PCR detection. The ME/TK cells showed significantly higher sensitivity to GCV than parental ME cells. ME/Tk and ME+ME/TK mixed cells were obviously suppressed with the gradational increase of GCV concentration. And the survival rate of ME+ME/TK mixed cells decreased with the increase of ME/TK ratio in mixed cells. It implied that TK/GCV system could kill not only tk+ cells but also untransduced tk cells in mixed cells, thus verifying the presence of bystander effect.

CONCLUSION: The above results demonstrate that HSV-tK/GCV system has obvious killing and bystander effect on cervical carcinoma cell line ME180.