Figure 9. IDO blockade increases the presence of IL-17⁺, but reduces the number of IFN-γ⁺ T cells in the lungs of A/J and B10.A mice.

Lymphocytes from lung infiltrating leukocytes (LIL) obtained from groups of 5–6 mice were gated based on forward/side scatters analysis. Gated cells were assessed for CD4⁺, CD8⁺, γδ⁺ and NKT⁺ markers using labeled antibodies. The presence of IL-17⁺, IFN-γ⁺ and IL-4⁺ T cells in the LIL was determined by intracellular cytokine staining at week 2 after infection. Lung cells were stimulated in vitro with PMA/ionomycin for 6 h, the last 4 h in the presence of brefeldin A, and subjected to intracellular staining for IL-17, IL-4 and IFN-γ. The results are representative of three experiments with equivalent results (*p<0.05, **p<0.01 and ***p<0.001).