Figure 1

IFN-γ and TNF-α greatly inhibit KSHV progeny production. (A) iSLK.219 cells were induced with Dox (0.2 μg/ml), and at the time of induction, each indicated cytokine/chemokine/growth factor was added to the culture. RANTES: 20 units/ml; IP-10, IFN-γ, TNFs, PDGF isotypes: 200 units/ml. At 3 days of treatment, infectious virus titer in the culture supernatant was determined. The means ± SEM of 5 independent experiments performed in duplicate are plotted. For the analysis of KSHV genome replication, iSLK.219 cells were induced as described in (A). At the time of induction, IFN-γ (B) or TNF-α (C) was added into the culture at 20 or 200 units/ml. At the indicated time points, cells were harvested and genomic DNA was prepared for quantitation of the number of the KSHV genomes by real-time PCR. Data are presented as means ± SEM from three independent experiments. *P < 0.01 by one-way ANOVA Tukey Method.