Fig. 2

IL-17A is essential for the development of Siglec-F⁺ neutrophils in the lungs of PPE-induced emphysema mice. A Representative FACS plot of the CD11b⁺ cell gate and the frequency and absolute cell number of Siglec-F⁺ neutrophils in the lungs of WT and IL-17A^KO mice 4 days after PPE instillation (n = 4 per group). B Experimental protocol for anti-IL-17A administration and PPE instillation. Representative FACS plot of the CD11b⁺ cell gate and the frequency and absolute cell number of Siglec-F⁺ neutrophils in the lungs of PPE-induced emphysema mice in which IL-17A was depleted (n = 5 per group). C The concentrations of IL-17A (black circles) and the frequencies of Siglec-F⁺ neutrophils (red circles) were assessed over 5 days following PPE instillation (n = 4 per group). D Experimental protocol for recombinant IL-17A administration and PPE instillation. The frequency of Siglec-F⁺ neutrophils in the lungs of WT and IL-17A^KO mice was assessed 4 days after PPE instillation, with or without recombinant IL-17A administration to IL-17A^KO mice (n = 5 per group). Unpaired two-tailed Student’s t test with Welch’s correction A, B, unpaired one-way ANOVA with Dunnett’s T3 post hoc test C, and unpaired two-way ANOVA with Tukey’s post hoc test D were used to measure significance. *P < 0.05, **P < 0.01; ns, not significant; error bars indicate the mean ± SD (SEM in C)