Figure 3.

Cellular responses elicited by SARS-CoV-2 SAM (LNP) vaccine in mice

Splenocytes of BALB/c mice (n = 5) immunized i.m. with SAM vaccine or saline control (mock) were harvested at 2wp2, stimulated ex vivo with a peptide mix specific to spike_FL-2P, and analyzed for CD8⁺ (A and C) and CD4⁺ (B and D) T cell responses by flow cytometry. The stacked bars (A and B) indicate distribution of the Tc0/Tc1/Tc2/Tc17 cytotoxic cells within the total CD8⁺ and the Th0/Th1/Th2/Th17 T helper cells within the CD4⁺ spike-specific T cells (mean ± SEM). Boolean combinations for spike-specific CD8⁺ and CD4⁺ T cell cytokines from splenocytes of individual immunized mice were background subtracted using Pestle software, and pies were generated using SPICE software (C and D). Each pie slice represents a proportion of the total spike-specific CD8⁺ or CD4⁺ T cell responses for a unique sub-population comprising CD107a, IFN-γ, IL-2, or TNF-α, as indicated in the legend. Bars under p value asterisks indicate significantly different group comparisons with ∗, p < 0.05; ∗∗, p < 0.01; ∗∗∗, p < 0.001; ∗∗∗∗, p < 0.0001.