Detection of S-RBD- and S1-specific IgG level in sera of mice immunized with S377-588-Fc protein.

<p>PBS was used as the control. (A) The titers of IgG specific to MERS-CoV S377-588-Fc (S-RBD) in sera (1:3,200 dilution) of mice at pre-immunization (pre-immune) and 10 days post-each vaccination. (B) Endpoint IgG titers in mouse sera from 10 days post-last vaccination. The data are presented as mean A450 ± standard deviation (SD) of five mice per group. Ability of IgG binding to MERS-CoV S-RBD (C) and S1 protein (D) was detected using mouse sera from 10 days post-last vaccination. Ability of IgG1 (E) and IgG2a (F) antibodies binding to MERS-CoV S-RBD was detected using sera from 10 days post-last vaccination. The data are presented as mean A450 ± SD of five mice per group at various dilution points.