Expression of WNV protein in baculovirus-transduced cells. (A) BHK-21 cells were transduced with Bac-G-prM/E (A-1), Bac-prM/E (A-2), Bac-G-EGFP (A-3), or Bac-EGFP (A-4), at a MOI of 100. At 48h post-transduction, the cells were fixed and immunofluorescence assay was conducted using monoclonal antibodies against WNV E-DIII protein, followed by fluorescein isocyanate-conjugated goat anti-mouse IgG. Fluorescent images were taken with a fluorescence microscope (400× original magnification). (B) BHK-21 cells were transduced with Bac-G-prM/E (lane 1), Bac-prM/E (lane 2), Bac-G-EGFP (lane 3), or Bac-EGFP (lane 4). Total cell lysates were prepared at 48 h post-transduction and subjected to Western blotting as described in Materials and Methods. Cell lysates from mock-transduced (lane 5) BHK-21 cells were used as a negative control. The positions of molecular size standards (in kilodaltons) were indicated. (C) Comparison of the transduction efficiency of Bac-G-prM/E and Bac-prM/E. BHK-21 cells were transcuced with Bac-G-prM/E (lane1-3) or Bac-prM/E (lane 4–6) at MOIs of 10, 50, and 100 and processed for Western blotting analysis.