Fig. 4
A single dose of ChinZIKV confers complete protection against ZIKV challenge in mice and monkeys. a Viral load in the sera of immunized mice after ZIKV challenge. The ChinZIKV immunized mice were challenged i.p. with 103 PFU of ZIKV. Viral RNA loads were determined by RT-qPCR. Dotted lines indicate the detection limit. The data are representative of at least three independent experiments, and error bars indicate the SD. Significance was calculated using a two-way ANOVA with multiple comparison tests (****P-value < 0.0001). b Four-week-old female BALB/c mice were immunized with 104 PFU of ChinZIKV (n = 3) or PBS (n = 2) as a control. On day 60 post immunization, the immunized mice were mated to 10-week-old male BALB/c mice. At embryonic day 13.5 (E13.5), the pregnant mice were infected with 105 PFU of ZIKV by the i.p. route. Viral RNA loads at days 1–3 post-infection were determined by RT-qPCR. Dotted lines indicate the detection limit. The data are representative of at least three independent experiments, and error bars indicate the SD. Significance was calculated using a two-way ANOVA with multiple comparison tests (****P-value < 0.0001). One-day-old suckling mice born to the ChinZIKV-immunized (n = 15) or PBS-immunized (n = 9) dams were challenged i.c. with 100 PFU of ZIKV. The mice were then monitored for clinical symptoms and mortality for 21 days. Asterisks indicate values that are statistically significant (***P-value < 0.001). c The PBS- or ChinZIKV-immunized monkeys were challenged s.c. with 103 PFU of ZIKV. Serum and body fluids were collected at the indicated times. Viral RNA amounts were determined by RT-qPCR. Dotted lines indicate the detection limit. d Cytokine amounts in the sera of the PBS- or ChinZIKV-immunized monkeys (n = 3, each group) at day 7 post challenge determined by a Monkey Cytokine Magnetic 29-Plex Panel kit. Experiments were performed in duplicate (error bars represent SD). Significance was calculated using the Student’s t test (**P-value < 0.01; ****P-value < 0.0001)
