Fig. 3
Assessment of protective efficacy induced by ChAdOx1 ZIKV vaccines. a BALB/c mice (n = 5) immunised with a single i.m. injection of ChAdOx1 ZIKV vaccines and naive mice were intravenously challenged with 105 VP of ZIKA-BR at week 4 after prime. Pre-challenge serum samples were collected for ELISA as shown. b Viral load in ZIKV-challenged groups was monitored for 7 days in sera to follow the onset of viraemia. Each blue line represents one mouse. c Assessment of various parameters of viraemia in groups vaccinated with ChAdOx1 ZIKV vaccines (100% = 6 out of 6 mice). d Pre-challenge reciprocal ELISA titres (Supplementary Fig. 4) were plotted against global ZIKV VL after ZIKV challenge and a comparison was made between ChAdOx1 Env ∆TM versus ChAdOx1 prME ∆TM (left) and ChAdOx1 prME versus ChAdOx1 Env (right). e ELISA OD 450 reads of serially diluted serum samples were plotted to assess the impact of ∆TM in antibody production. Antibody production by ELISA in pre-challenge sera was replicated two times. f Immunofluorescence analysis of Vero cells expressing the ZIKV immunogens (green) to assess subcellular staining and distribution. Antigen was detected using a commercial anti-flavivirus antibody. Blue (DAPI) represents the nucleus and scale bar is 20 μm. Cell transfections were performed in technical duplicates in two biological replicates. g Kinetics of ZIKV envelope antigen expression in HEK-293 cells by western blot. Antigen was detected using an anti-ZIKV monoclonal antibody in both, non-concentrated supernatant and cell extracts. Red arrows, ZIKV envelope. Actin was used as a loading control. Expression of antigen was verified in three biological replicates. Uncropped blots are shown in Supplementary Fig. 5
