Indoleamine 2,3-dioxygenase–expressing fibroblasts suppress infiltration of IL-17+ CD4+ T cells in skin, ear, and lymph node of psoriatic mice. Upon euthanizing mice on day 9, the dorsal skins, right ears, and lymph nodes were collected. After obtaining single-cell suspensions, cells were stimulated in Cell Stimulation Cocktail overnight. T cells were stained for their surface and intracellular markers in 1% fetal bovine serum + phosphate buffered saline–containing phycoerythrin-conjugated anti-CD4 and eFleur-conjugated anti-IL-17. (a) Representative flow cytometry plots of gating. (b) Representative flow cytometry plots of IL-17+ CD4+ T cells in skin, ear, and lymph nodes. (c to e) Quantitative analysis of IL-17+ CD4+ T cells in skin, ear, and lymph nodes, respectively. (f to h) Mean fluorescence intensity (MFI) of IL-17 in skin, ear, and lymph nodes, respectively. Pso. ear, right ear which has received 5 mg imiquimod cream. The significant differences have been indicated by asterisks (*; P < 0.01; n = 3).