Extended Data Figure 5. A single dose of mRNA-1273 elicits robust antibody responses.

BALB/cJ mice were immunized with 0.1 (blue), 1 μg (red), or 10 μg (purple) of mRNA-1273. Sera were collected 2 (open circles) and 4 (closed circles) weeks post-immunization and assessed for SARS-CoV-2 S-specific total IgG by ELISA (a) and neutralizing antibodies against homotypic SARS-CoV-2 pseudovirus (b). (c) S-specific IgG2a and IgG1 were also measured by ELISA, and IgG2a to IgG1 subclass ratios were calculated. Dotted line = assay limit of detection. (a-b) Doses were compared 4 weeks post-boost, and timepoints were compared within each dose level.