Figure 2A showed that transfection USP18 plasmid led to a remarkable increase of USP18 mRNA expression. We found that USP18 over-expression increased DENV-2 RNA levels in Hela cells and culture supernatants at 48 h post-infection (Figures 2B,C). Western blot further confirmed the over-expression of USP18 and its upregulation effect on DENV-2 capsid protein expression compared to the empty vector (mock) group (Figure 2D). Here, USP18 is linked to infection.