Abstract
Background and Objectives
Evaluation of cell survival is important in cellular studies and the result is decisive for the application of the test substance. Different methods are used to evaluate cell survival and the correlation between methods is important. Here, Vero cell line was used to evaluate the effects of HSV-1 virus on cell survival. Cell survival after HSV-1 infection using sensitive colorimetric methods of 3-, 4-, 5-dimethylthiazole-2-yl, -2, 5-diphenyltetrazolium bromide (MTT), and Trypan Blue on Vero cell line was examined.
 
Materials and Methods
A qualitative study was performed on Vero cell line infected with HSV-1 virus with logarithmic dilutions10^-1 to 10^-5 dilutions and time intervals of 0, 4, 8, 18 and 24 hours and the s in DMEM containing 2% Fetal bovine serum (FBS). Then cell viability by MTT and Trypan tests was examined . The survival percentage was used to plot the survival curve of the assays.
 
Results
Different viral dilutions were used to determine the infectious dose of 50% (TCID50) of HSV-1virus with invert microscope. Acyclovir at a concentration of 50 mg/mL was compared as drug control for MTT and Trypan Blue. The results of regression analysis showed cell survival. Linear, positive and significant correlation was observed between the methods that showed a correlation between MTT and Trypan Blue methods (p< 0.001, r = 0.9(
 
Conclusions 
The results showed that both methods can be used to determine cell survival and the results of MTT can be confirmed by Trypan Blue method.