Fig. 8

Protective efficacy of the inactivated EV-A71 + EV-D68 vaccine with or without PS-G as adjuvant in the EV-D68 or EV-A71 infection mouse model. The passive sera transfer and virus challenge schedules are shown. Briefly, 2-d-old ICR mice were i.p. injected with 20 μL anti-PBS, anti-EV-A71 + EV-D68, or anti-EV-A71 + EV-D68 + PS-G sera. After 6 h, the suckling mice were intracerebrally (i.c.) administered with RD medium, a EV-D68 (CDC_NO 2016-05298), or f EV-A71 (MP4). Mock mice were given medium only. b, g Representative images showing symptoms of healthy mice in the EV-A71 + EV-D68 or EV-A71 + EV-D68 + PS-G immunized group and mice with limb paralysis in the PBS-immunized group on day 9 post-infection with EV-D68 or EV-A71. Mice were monitored daily for c, h clinical score and d, i survival rates for 14 d following infection. Clinical scores were graded as described in “Methods”. e, j Brain, spinal cord, and muscle were collected after infection, and viral loads within the indicated tissues were determined using real-time quantitative PCR (qRT-PCR). The levels of expression were normalized to those of GAPDH. All data are expressed as the mean ± SEM. *p < 0.05, **p < 0.01, ***p < 0.001