Fig. 4: RBD-CLP vaccines induce high antigen-specific antibody titers in mice.
Serum samples were obtained before vaccination (pre-bleed) and two weeks after primary (1st bleed) and boost (2nd bleed) vaccination, respectively. ELISA results are depicted both as raw serum dilution curves (a, c) as well as the area under curve (AUC) and the geometric mean/SD (b, d). a Serum dilution curves and b geometric mean titer/SD (RBDc 1st bleed: GMT = 0.289; RBDc 2nd bleed: GMT = 0.4369; RBDc-CLP 1st bleed: GMT = 2.252; RBDc-CLP 2nd bleed: GMT = 8.515) of total anti-SARS-CoV-2 spike (aa35-1227) IgG antibodies detected in sera from BALB/c mice immunized intramuscularly with soluble RBDc (prime 2 µg/boost 2 µg) (n = 4) or CLP-displayed RBDc (RBDc-CLP) (prime 1 µg/boost 1 µg) (n = 4). c Serum dilution curves and d geometric mean titer/SD (RBDn 1st bleed: GMT = 0.2578; RBDn 2nd bleed: GMT = 2.727; RBDn-CLP 1st bleed: GMT = 4.427; RBDn-CLP 2nd bleed: GMT = 12.44) of total anti-SARS-CoV-2 spike (aa35-1227) IgG antibodies detected in sera from Balb/c mice immunized intramuscularly with soluble RBDn (prime 5 µg/boost 5 µg) (n = 4) or CLP-displayed RBDn (RBDn-CLP) (prime 6.5 µg/boost <0.1 µg/boost 6.5 µg) (n = 4). e IgG subclass profile in sera from mice (n = 4) immunized (prime-boost) with the RBDn-CLP vaccine. IgG1 GMT = 7.108; IgG2a GMT = 5.814; IgG2b GMT = 4.390; IgG3 GMT = 1.088. f IgG subclass profile in sera from mice (n = 4) immunized (prime-boost) with the soluble RBDn vaccine. IgG1 GMT = 1.615; IgG2a GMT = 0.3586; IgG2b GMT = 0.4696; IgG3 GMT = 0.4690.
