Figure 2.

Generation of multiple flavivirus SRIPs with different prME plasmids. (a) Luciferase activity of SRIPs produced by transfection of 293T cells with replicon plasmid and structural protein-expression plasmids. Each plasmid used for transfection is indicated. The supernatants of transfected cells collected at 3 days post-transfection were used to inoculate Vero cell monolayers. Luciferase activity of infected cells was subsequently determined at 3 days post-infection. (b) Relationship between luciferase activity and a number of infected cells. WNV-SRIPs were serially diluted (2-fold dilutions) and used to inoculate Vero cells. Luciferase activity and a number of cells stained with anti-NS1 antibody were plotted. The dotted line indicates the linear regression line. The coefficient of determination (R²) is displayed in the graph. (c) Luciferase activity of SRIPs produced by transfection of 293T cells with replicon plasmid and structural protein-expression plasmids. Each prME plasmid used for transfection is indicated. The supernatants of transfected cells collected at 3 days post-transfection were used to inoculate Vero cell monolayers. Luciferase activity of cells was subsequently determined at 3 days post-infection.