Fig. 6

Impact of IL-33 on cell recruitment and histological response in the spleen of BALB/c mice during infection with L. donovani. The total numbers of each cell type were quantified by flow cytometry, in mice treated or not with rIL-33 (a–d). Quantification of B lymphocytes (CD19+) (a) and Spearman correlation of the number of B lymphocytes and ST2+ B lymphocytes (b), quantification of CD3+/CD4+ T cells (c), and CD3+/CD8+ T cells (d) per organ. Data are expressed as mean ± SE for each group of mice (4–5 mice per treatment group for each time point) (*P < 0.05; 2-way ANOVA comparison). Spleen weight at indicated time post-infection in BALB/c wt and ST2-KO mice (e) and BALB/c mice treated with rIL-33 or untreated (wt) (g). Quantification of germinal centers (GC) areas by microscopy using NDP view 2.4.26® software in BALB/c wt and ST2-KO mice (f), BALB/c mice treated with rIL-33 or untreated (wt) (h). Data are expressed as mean ± SE for each group of mice (4–5 mice per group for each time point) (*P < 0.05, **P < 0.01, ***P < 0.001, with 2-way ANOVA comparison between groups of mice and Mann-Whitney test between time points). Splenomegaly was inversely correlated to IL-33 mRNA expression in BALB/c wt (Spearman correlation)