Fig. 3.

S-RBD nebulization triggers an intense TLR4 receptor-dependent lung inflammation in mice. The effect of S-RBD nebulization on TNF-α (A) and IL-6 (B) secretion from C57 (gray bars) and Lps del (red bars) animals. TNF-α and IL-6 secretion was measured in BALs by ELISA at different time points post-nebulization. Data are presented as mean ± SEM. **p < 0.01 and ***p < 0.001 vs 0 h post-nebulization using Two-way ANOVA and Dunnett post hoc test, n = 5 animals for each condition. S-RBD: RBD of the Spike protein; TNF-α: Tumor necrosis factor-alpha; IL-6: Interleukin 6; BALs: Bronchoalveolar lavages; ELISA: enzyme-linked immunosorbent assay