FIG 2.
Triggering of endosomal TLR7 and TLR9 but not TLR3 inhibits expression of the lytic MHV 68 ORF50 gene and reduces viral particle shedding, while TPA or NF-κB inhibitor Bay 11-7082 increases spontaneous reactivation. (A) S11 cells were mock treated or treated with TLR3 ligand poly(I·C), TLR7 ligand R848, TLR9 ligand CpG ODN 1826, or TPA or a combination of TLR ligand followed by TPA 2 h later. At 24 h after the beginning of treatment, expression levels of the MHV 68 lytic ORF50 gene were analyzed by qPCR, normalized to GAPDH, and plotted relative to untreated control results (black bars). Viral titers in the supernatants of treated cells were measured by a plaque assay (white bars). (B) S11 cells were mock treated or treated with TPA, R848, CpG ODN 1826, or NF-κB inhibitor Bay 11-7082 or a combination thereof. At 24 h after treatment, expression levels of the MHV 68 lytic ORF50 gene were analyzed by qPCR (black bars). Viral titers in the supernatants of the treated cells were measured by a plaque assay (white bars). Data shown in panels A and B are means ± SD of the results of three independent experiments. Statistics were calculated using an unpaired t test (*, P < 0.05; **, P < 0.01).