Extended Data Figure 7. mRNA-1273 elicits Th1-skewed responses compared to S protein adjuvanted with alum.

BALB/c mice were immunized at weeks 0 and 2 weeks with 1 (red) or 10 μg (purple) of mRNA-1273 or 10 μg of SARS-CoV-2 S protein adjuvanted with alum hydrogel (orange). (a-b) Sera were collected 2 weeks post-boost and assessed by ELISA for SARS-CoV-2 S-specific IgG1 and IgG2a. Endpoint titers (a) and endpoint titer ratios of IgG2a to IgG1 (b) were calculated. (c-d) Splenocytes were also collected 4 weeks post-boost to evaluate IFN-γ IL-4, IL-5, and IL-13 cytokine levels secreted by T cells re-stimulated with S1 (c) and S2 (d) peptide pools, measured by Luminex. Dotted line = assay limit of detection. IgG1 and IgG2a/c (a) were compared at each dose level. (c-d) For cytokines, all comparisons were compared to PBS-immunized mice.