CD4 and infection: To investigate whether IL-22 deficiency affects T cell mediated immunity, we performed flow cytometry of cellular suspensions obtained from lungs of WT and Il22−/− mice over the course of infection with H. capsulatum. The gating hierarchy used to identify lymphocytes is illustrated in Figure S4 and one representative plot of percentages of T cell subsets is shown in Figure 4A. In the absence of IL-22, we observed reduced numbers of IFN-γ- or IL-10-producing CD4+ T cells, but not IL-17-producing CD4+ T cells at seven days post-infection (Figure 4A—left panel and 4B—upper panels).