Figure 4.

Reducing ADE activity of infection enhancements by glycan-masking ZIKV E antigen. (A) Glycan-masking ZIKV E antigen. The structure of ZIKV E protein (PDB: 5JHM) are generated using the PyMOL molecular graphics system (Schrödinger, LLC). Glycan-masking Ad-ZprME mutants by introducing additional N-linked glycosylation motifs on bc loop (green), FL (blue), and ij loop (red). (B) A list of four glycan masking mutants constructed by introducing additional N-linked glycosylation motifs on ZIKV E proteins. (C) BALB/c mice were immunized with two doses of Ad-ZprME, Ad-ZprME-74, Ad-ZprME-105, Ad-ZprME-248, and Ad-ZprME-252 within a two-week interval, and antisera were collected 2 weeks after second-dose immunization. Serum total IgG titers against recombinant ZDIII were measured using ELISA coated with ZIKV. (D) Neutralizing antibody titers against ZIKV were analyzed by PRNT assay and calculated for PRNT₅₀ values (E) Antisera tested for ADE activity in K562 cells against DENV2 virus infections. The mAb 4G2 was the positive control. The fold enhancement was calculated by dividing the percentage of infected cells with antisera by the percentage of infected cells without antisera. Data were analyzed using one-way ANOVA. (**, p <0.01).