Generation of recombinant baculovirus displaying RSV G The recombinant baculovirus expressing RSV G coding sequences under the control of the polyhedrin promoter, Bac-RSV/G, was generated using Bac-to-Bac system with a pFastBac-1 plasmid as shown in Fig. 1A . To examine whether Bac-RSV/G express and display RSV G in the virus particle, western blotting analysis was performed with sucrose gradient-purified baculoviruses. Using the G-specific monoclonal antibody, specific bands of approximately 70 kDa to 90 kDa were detected in the purified Bac-RSV/G particles, but not in Bac-control virus particles (Fig. 1B) . As a positive control, purified RSV particles produced in HEp-2 cells were used and slightly higher molecular weight bands were detected (Fig.  1B) . The size difference might be due to different patterns of glycosylation between insect cells and human cells.