Fig. 2

mRNA-1273 vaccine intratumoral treatment reduces tumor growth and increases CD8⁺ T cells in the tumor. (A) B16F10 tumor growth curves and tumor volume measurements at (B) 4 days and (C) 8 days following a 20 µL intratumoral injection of 3 µg mRNA-1273, empty LNP or PBS (n = 5 mice/group, n = 15 mice total). Day 0 represents the time of IT injection when tumors reached 5 mm in diameter. (D) Representative intravital image of tumor (GFP, green) and CD8⁺ T cells (CD8a⁺, red) prior to (Pre) and 24 h post (24 h) 10 µL IT injection of 1.5 µg mRNA-1273 or PBS; scale bar represents 100 μm. (E) Corresponding quantification of the number of CD8⁺ T cells in the tumor (n = 5 mice treated with mRNA-1273, n = 4 mice treated with PBS, n = 9 mice total; n = 3 images per mouse per time point). Flow cytometry analysis of (F) CD8⁺ T cell subsets within the tumor 4 days post IT injection (n = 3 mice/group, n = 9 mice total). Data shown as mean (SD); one-way or two-way ANOVA followed by Tukey’s multiple comparison test, *p < 0.05, **p < 0.01, ***p < 0.001, ****p < 0.0001.