Fig 6. TLR7/9 is required to stimulate optimal levels of IFNγ and restrict IL17 production.

Lungs of mock-infected or infected wild-type and TLR7/9^-/- mice were harvested, homogenized, and evaluated for cytokine levels (A) TNFα, (B) IL6, (C) IL17a, and (E) IFN-γ. (D, F-H) Intracellular cytokine staining on lung cells was measured to detect IFN-γ and IL17A production in γδ T cells, NK cells, CD4⁺ and CD8⁺ T cells isolated from the lung. Cells were defined as: CD4⁺ T cells (CD45⁺CD3ε⁺CD4⁺), CD8⁺ T cells (CD45⁺CD3ε⁺CD8⁺), γδ T cells (CD45⁺CD3ε⁺γδTCR⁺), NK cells (CD45⁺CD3ε^-NK1.1⁺). (G) Total number of T cells per lung and (H) the percentage of T cells that were CD69⁺ were calculated. (I-J) WT, TLR7/9^-/-, IFNAR^-/-, and Batf3^-/- mice were either mock-infected or infected with 3x10⁵ Histoplasma yeasts. Lungs were harvested, homogenized, and evaluated for levels of (I) IL12 p70 and (J) IFNγ. All error bars indicate SD. *p < 0.05; **p < 0.001; p values were determined by ANOVA.