Fig 1: TG2-dependent chemokine production in keratinocytes is critical for IL-17-producing CCR6+ γδT-cell and neutrophil dermal infiltration.a, b Effect of DMSO- or IMQ-treated WT- or TG2−/−-CM on CCR6+ γδT-cell (a) and CD11b+ Ly-6G+ cell (b) migration according to Transwell migration assays. Flow cytometric analysis of the percentage of cells migrating toward the CM in the presence or absence of anti-CXCL1 (a) and anti-CCL20 (b) antibodies (n = 3/group). c, d WT and TG2−/− mouse-derived CCR6+ γδT-cell (c) and CD11b+ Ly-6G+ cell (d) migration in response to recombinant mouse CCL20 and CXCL1, respectively. Data represent the mean ± SEM (n = 3/group). *p < 0.05; **p < 0.01. e, f Cells were isolated from the back skin of WT and TG2−/− mice treated with IMQ for four consecutive days and analyzed by flow cytometry. Representative flow cytometric profiles of CCR6+ γδTCRlow cells (e) and CD11bhigh Ly-6G+ cells (f). The percentage of cells is shown. Data represent the mean ± SEM (n = 9/group). g Skin sections were immunostained with CCR6 (green)- and IL-17 (red)-specific antibodies. Nuclei were stained with DAPI (blue). Scale bar, 100 μm. h–j Back skin was separated into epidermis and dermis and analyzed by RT-PCR for IL-17-producing γδT-cell markers (h) (Ccr6 and Il23r), IL17 and related cytokines (i) (Il17a, Il17f, and Il22), and myeloid cell-derived cytokines (j) (Il12a and Il23a). Data represent the mean ± SEM (n = 11/group). *p < 0.05; **p < 0.01 vs. WT mice.