Colony * 
(figures 5 and 6). Of note is the approximately 1% GCV resistant colonies in some 
instances observed at high GCV concentrations. The significance of these cells will be 
discussed below. 
NIH 3T3 
200 -i 
E 100 - 
u 
0 0 005 0.05 0.5 5 50 
[GCV1 
kbalb 
kbalb-LNL 
kbalb-STK 
kbalb-uTK 
1GCV] 
200 
6 
■ SK-N-MC 
■ SK-N-MC-STK 
In addition, two ovarian carcinoma cell lines, SKOV-3 and PA-1, were transduced with 
the STK retroviral vector and exposed to varying concentrations of ganciclovir. Figures 
7 and 8 demonstrate a similar cell toxicity as is seen in experiments above. 
[GCV] 
[GCV] 
[580] 
Recombinant DNA Research, Volume 15 
