Figure 3.

Recall of immune responses to SARS-CoV-2 after viral challenge

(A) Study outline.

(B and C) IgG binding ELISA. SARS-CoV-2 S1+S2 (B) and RBD (C) protein antigen binding of IgG in diluted NHP sera collected prior to challenge and post-challenge in INO-4800-vaccinated (right panels) and naive animals (left panels).

(D) Live virus neutralization.

(E) Pseudo-neutralization assay showing the presence of SARS-CoV-2-specific neutralizing antibodies against the D614 and G614 variants of SARS-CoV-2 before and after viral challenge.

(F) T cell responses were analyzed pre- and post-challenge with SARS-CoV-2 virus by IFN-γ ELISpot in PBMCs stimulated with overlapping peptide pools spanning the SARS-CoV-2 spike protein. Individual animal responses are depicted by open symbols and filled symbols represent median values. ∗∗p < 0.01 Mann-Whitney test.

See also Figures S3 and S4.