FIG 4 .

Effect of α-GalCer treatment during the resolution phase of influenza on secondary bacterial infection. (A, left panel) The frequencies (±SD) of pulmonary conventional DCs (cDCs) and monocyte-derived DCs (MoDCs) among CD45⁺ cells were determined in mock-infected and IAV-infected (14 dpi) mice. (Right panel) CD1d expression on conventional DCs is represented. Ctl, control. (B) Analysis of the frequency of pulmonary iNKT cells expressing IFN-γ and IL-17A from IAV-infected mice (14 dpi) in response to i.n. α-GalCer treatment (n = 10 to 12, three pooled experiments, mean ± SD). (C) IAV-infected mice were treated with α-GalCer (2 µg/mouse i.n.) 16 h before the S. pneumoniae challenge (14 dpi). The numbers of CFU in lungs and spleen were determined 30 h later. The solid lines correspond to the median values. Shown are cumulative data from two independent studies. ns, not significant. *, P < 0.05; ***, P < 0.001 (one-way ANOVA Kruskal-Wallis test for panel B).