Fig. 6.

Production of infectious EBV particle in response to ZRL₅P₄. The HONE-1-EBV cell line, which expresses GFP to indicate the presence of the EBV genome, was used. This cell line was treated with 10 µM ZRL₅P₂ or ZRL₅P₄ for 4 d, and the viral particles released in the culture medium were detected by the Raji cell assay. The culture medium was added to Raji cells for 3 d, and GFP expression reflects the reinfection by the HONE-1–released EBV particles. (A) Representative results are shown. The GFP signal was detected by ultraviolet light exposure, and the cell morphology was captured by phase-contrast light microscopy and the bright-field image was merged with the GFP image. Magnification, 400×. (Scale bars, 100 µm.) (B) Relative average viral titer in response to ZRL₅P₂ or ZRL₅P₄ was compared with the solvent control (DMSO). The Raji cell assay was performed in triplicate for each treatment. **P < 0.01, statistically significant difference. Data are expressed as the means ± SD. (C) Representative images of immunofluorescent analysis of Dicer1 and PML in HONE-1-EBV cells in response to 10 µM ZRL₅P₂ or ZRL₅P₄. The nuclei were counterstained with DAPI and indicated in blue. (Scale bars, 50 µm.) (D) Comparison of the number of Zta-positive cells after treatment with ZRL₅P₄ in the presence versus the absence of Dicer1. HONE-1-EBV and NPC43 were included. Gene silencing of Dicer1 was achieved by siRNA transfection. Zta was detected by immunofluorescent analysis. Control siRNA (siCTL) was used as a negative control. Relative percentage of Zta-positive was compared against the DMSO solvent control in the siRNA control cells. *P < 0.05.