Figure 3.

DENV DNA vaccine construction

(A and B) Schematic representation of DENV DNA vaccine and cloning strategy. Synthetic DENV expression cassette was inserted into the pVAX1 expression vector between NheI and HindIII under the control of the cytomegalovirus (CMV) immediate-early promoter. (C) RT-PCR of RNA extracts from HEK293T cells transfected with DNA DENV vaccine or pVAX1. GAPDH is used as an internal expression normalization gene. Data are representative of three independent experiments. p values were determined by Student’s unpaired t test; ∗p ≤ 0.05. (D–F) Analysis of in vitro expression of EDIII (D), NS1 (E) protein, and full-length expressed protein (F) after transfection of 293T cells with DDV or plasmid control by western blot. (G) Immunofluorescence staining of 293T cells transfected with 5 μg/well DDV or plasmid control. Expression of antigen was measured using anti-DDV immune sera. Cell nuclei were counterstained with DAPI. The vector map was created with BioRender.com.