Method for measuring antiviral susceptibility of herpes simplex virus and establishment of resistant strain

Objective:To investigate the method for measuring antiviral susceptibility and to establish an acyclovir-resistant herpes simplex virus.Methods:HSV-Ⅰ was inoculated on African green monkey kidney (VERO) cells,ACV and GCV was added to the medium in various concentrations. After 72 hours incubation, plaques were counted and the 50% effective dose (ED 50)was calculated. HSV-Ⅰwas incubated in the presence of ACV for 10 passages. The ED 50 of ACV was determined after the 3,5 7and 10 passage.Results:The ED 50 of ACV and GCV to wild HSV-Ⅰwas 142.0×10 -9 mol·L -1 and 294.0×10 -9mol·L -1. In the presence of ACV, emergence of drug resistance was observed after passage 7 with ED 50 82 times that of the wild strain. After the 10 th passage the ED 50 was 170 times that of the wild strain. Conclusions:Plaque reduction assay is an efficient method for determination of antiviral drug susceptibility of HSV and the establishment of ACV-resistant strain is essential for the study of resistance.