ANTIVIRAL EFFECT OF SHORT HYPERTHERMIC TREATMENT AT SPECIFIC STAGES OF VESICULAR STOMATITIS-VIRUS REPLICATION CYCLE

Starting from the observation that the antiviral activity of cyclopent enone prostaglandins is associated with the synthesis of a 70K heat sh ock protein (HSP70), we have analysed the effect of short hyperthermic treatment (HT) on HSP70 induction and virus production in monkey epit helial cells during the replication of vesicular stomatitis virus (VSV ). The heat shock response, as determined by HSP70 synthesis, appeared to be unaltered in VSV-infected cells in the first 4 h following viru s infection, after which time it started to decline. No induction of H SP70 synthesis was observed when HT was applied 8 h after VSV infectio n. A 20 min HT at 45-degrees-C was effective in suppressing VSV multip lication by more than 90 % when applied at specific stages of the viru s replication cycle. Synthesis of virus proteins was not affected by H T, indicating that the target for the treatment is a post-translationa l event. The HT-induced block of virus replication appeared to be asso ciated with inhibition of VSV G protein maturation and HSP70 induction .