Fig. 2

Antiviral effect of CST against A/Fort Monmouth/1/1947(H1N1). a and b MDCK and THP-1 cells were infected with A/Fort Monmouth/1/1947(H1N1) at 100TCID₅₀, and CST was added after viral infection. RBV is the positive control. At 24 h post infection, cells were frozen and melt, and virus from the supernatant was harvested. Viral titers were quantified by cytopathic effect assay. Results were expressed as log₁₀ values of the mean viral load ± SD. c, d, e, and f MDCK and THP-1 cells were infected with 100TCID₅₀ influenza virus. The medium was changed 2 h after virus infection, and cells were treated with DMSO or CST. The cells were harvested 18 h after infection for Western blot or 12 h after infection for qRT-PCR. **p < 0.01 significantly different from the Con group. Data are expressed as mean ± SD, and the results represent the average of three independent experiments. g MDCK cells were infected with the 100TCID₅₀ influenza virus. After infection for 2 h, MDCK cells were treated with CST or RBV for 18 h. The cells were stained with an anti-M2 antibody and imaged by immunofluorescence microscopy. M2 staining is shown in green. Nuclei stained by Hoechst are shown in blue