Supplementary Figure 1: Allergic inflammation in AhR-CA mice.

(a) Gate strategy for assessing allergic inflammatory cells in the skin of AhR-CA mice. CD4⁺ T cells were gated on CD45⁺SSC^lowFSC^lowCD3⁺CD4⁺ cells. Mast cells were gated on CD45⁺CD3^–B220^–SSC^hiFSC^hiCD117⁺FcɛRIα⁺. ILC2s were gated on CD45⁺SSC^lowFSC^lowLin^–(CD3^–CD5^–B220^–CD11b^–Gr-1^–NK1.1^–FcɛRIα^–) CD25⁺IL-33Rα⁺CD127⁺KLEG1⁺ cells. Eosinophils were gated on CD45⁺CD3^–B220^–SSC^hiFSC^lowCD11b⁺Siglec-F⁺ cells. Basophils were gated on CD45⁺CD3^–B220^–CD117^–CD49b⁺FcɛRIα⁺ cells. (b) Number of inflammatory cells detected in the skin of 5 AhR-CA mice and that of 5 WT littermates. Dots represent individual mice. (c) Relative expression of barrier-related genes in the epidermis of 5 AhR-CA mice and 5 WT littermates; box-and-whisker plot (line, median; box, 25th to 75th percentiles; bar, minimum to maximum). (d) Relative expression of Tslp, Il33 and Cyp1a1 in AhR-CA overexpressing keratinocytes; each dot represents an independent sampling, n=3. (e) AhR-CA ChIP-qPCR results from 3 independent samplings. (f, g) Immunostaining of the skin for TSLP (f) and IL-33 (g). Dotted line, the epidermis-dermis boundary; scale bar, 50 µm for f and 100 µm for g; representative images of 3 mice each. (h) Intracellular cytokine staining of CD4⁺ T cells isolated from regional lymph nodes of AhR-CA mice and WT littermates (5 mice each). (i) Dot-plot presentation of the intracellular cytokine staining observed in h. Dots represent individual mice. Data in b, d, and i; lines represent the mean; unpaired t-test; *p <0.05, **p < 0.01 and ***p<0.001.