FIG 7.

Enhancement of VLP secretion and immunogenicity by manipulation of ectodomain of E protein. (A) An increase in the VLP secretion titer in pVD2-Cosmopolitan/Asian 1 EDI-II-transfected COS-1 cells after replacement of the EDI-II gene of the WT pVD2-Cosmopolitan plasmid vector with the corresponding gene segment from the pVD2-Asian plasmid was determined by ELISA. ****, P < 0.0001. (B) pVD2-Cosmopolitan/Asian 1 EDI-II-vaccinated mice exhibit a larger total IgG antibody response. **, P = 0.0017. (C) Improvement of FRμNT titers against the different DENV-2 genotypes by sera from pVD2-Cosmopolitan/Asian 1 EDI-II-vaccinated mice. *, P = 0.0195; **, P = 0.0031; ***, P = 0.0004. All data represent the means ± SEMs of two independent experiments. Means were analyzed by an unpaired t test, and significance (P < 0.05) is indicated with asterisks.