Intracellular pools of thymidine reduce the antiviral action of acyclovir

Abstract

Acyclovir inhibits herpes simplex virus (HSV) infections better in human fibroblasts than in green monkey kidney cells. Thymidine and acyclovir compete for the active site of HSV thymidine kinase. Large intracellular pools of thymidine found by high-performance liquid chromatography (HPLC) seemed to be responsible for the reduced activity of acyclovir. Such intracellular thymidine pools could not be measured previously, and the HPLC technique may help in evaluating the expected efficiency of acyclovir in cells and tissues prior to treatment.