Fig 4.

The JNK inhibitor SP600125 interferes with VSV infectivity. (A) Viral titers obtained from DMSO-, SP600125 (JNKi)-, and IFN-treated cells were compared to the corresponding genome copy numbers. Infection was performed for 16 h, and viral genomic RNA in the supernatants was analyzed by real-time PCR, whereas the viral titer was determined by TCID₅₀ assay. Upon treatment with SP600125, the difference between viral titers and genome copy numbers was significant (*, P < 0.05). (B) Semipurified viruses obtained from DMSO-, SP600125 (JNKi)-, and IFN-treated cell supernatants by ultracentrifugation were used to determine VSV protein expression by Western blotting. Viral titers of the samples shown are listed at the bottom. (C) Determinations of growth kinetics on HCC cells were performed in the presence of vehicle (DMSO) or SP600125 (JNKi). Cells were infected with VSV at an MOI of 0.1, and viral titers were determined by TCID₅₀ analysis at the indicated time points. Mean values and standard deviations from triplicate experiments are shown.