Fig. 6
Effect of the EV-A71 + EV-D68 bivalent vaccine with or without PS-G or CpG as adjuvant on the levels of EV-D68- and EV-A71-specific IgG and IgA, and neutralization titre against infection by different enteroviruses in the sera of mice. The levels of a EV-D68-specific IgG and IgA and b EV-A71-specific IgG and IgA in the sera of mice after the third intranasal immunization were measured using ELISA. Sera were serially diluted (23–212), mixed with c EV-D68 and d EV-A71 virus, and used to infect RD cells. After 4 d, the highest dilution that resulted in the virus producing no cytopathic effect was considered to be the neutralization titre. All data are expressed as the mean ± SEM. *p < 0.05, **p < 0.01, ***p < 0.001