Fig 2: Subcutaneous xenograft model to investigate the effect of IL-17A. a Time course of tumor growth at day 14 in the IL-17A-treated group and the control group. Results are expressed as the mean ± SD (n = 10). b Microscopic view of mouse xenograft tumors. Histological examination using H&E staining. Fibrous tissue was determined by Azan staining. Immunohistochemical examination of a-SMA was performed. c Fibrous tissue was measured. Data are expressed as the mean ± SD in three representative regions at ×200 high-power magnification. d A a-SMA positive lesion was measured and is shown as a percentage (a-SMA-positive area/whole section area). Data are expressed as the mean ± SD in three representative regions at ×200 high-power magnification

Fig 3: IL17A transcript-positive leukocyte spots are characterized by Th17 markers and IL17A tissue response genes.a UMAP (Uniform Manifold Approximation and Projection) plot showing the distribution of spots within the analyzed diseases AD, LP and Pso and non-lesional (NL) skin. b ST spots expressing IL17A transcripts and leukocyte marker genes and their location in epidermis or dermis. IL17A-positive spots are highlighted in blue. c Volcano plot analysing the gene expression profile of IL17A transcript-positive leukocyte (IL17A+) versus IL17 transcript-negative leukocyte (IL17A-) spots. Coordinates for IL17A (38.4/168.3) are not shown. Benjamini–Hochberg was used to determine statistical significance. d Violin plots of selected genes in IL17A transcript-positive leukocyte (IL17A+) and IL-17A transcript-negative leukocyte (IL17A-) spots indicate the expression of gold standard genes. e Pathway enrichment analysis of genes co-expressed with IL17A in spatial spots. LP lichen planus, AD atopic dermatitis, Pso psoriasis, ST spatial transcriptomics.

Fig 4: Low numbers of disease-driving cytokine transcripts are expressed in lesional skin of ncISD.a Representative ST sections for psoriasis with IL17A-, AD with IL13, and LP with IFNG transcript-positive spots (Ø55µM). b, d UMI-counts of IFNG (white), IL13 (dark grey) and IL17A (black) expressed in the manually annotated tissue layers ‘upper, middle, and basal epidermis’ and ‘dermis depth 1-7’ in non-lesional (b) and lesional skin (d) of all investigated samples (n = 82). GAPDH serves as a housekeeping gene (HkG) (light grey). c, e Total cytokine (IFNG (white), IL13 (dark grey) and IL17A (black)) and GAPDH (light grey) UMI counts in all non-lesional (c) and lesional (e) skin sections. f In situ hybridization for IFNG, IL13 and IL17A in representative stainings of LP (upper left panel), AD (upper right panel) and psoriasis (lower panel). Scale bar indicates 500 µm; red circles represent the size of a spot (Ø 55 µm) and indicate the positivity for cytokine mRNA. g Quantification of cytokine-positive cells per in situ section. Given are IFNG transcript-positive cells in LP (n = 5), IL13 transcript-positive cells in AD (n = 3) and IL17A transcript-positive cells in psoriasis (n = 5). h–j scRNA-seq analysis of psoriasis biopsies (n = 2, 2187 cells) indicating the UMI count of IFNG (178 cells), IL13 (9 cells), and IL17A (61 cells) per cell in CD4 or CD8 co-expressing cells. k–m Bulk sequencing analysis of non-lesional and lesional LP (n = 30) (IFNG), AD (n = 48) (IL13), and psoriasis (n = 90) (IL17A) biopsies indicating the total UMI counts for IFNG, IL13, and IL17A, respectively, in each biopsy. n–p UMI counts for IFNG, IL13, and IL17A in ST sections separated by disease (each dot represents one section) (LP n = 22, AD n = 18, Pso n = 18). Statistical significance was determined using One-Way Anova and Turkey’s multiple comparisons test without FDR correction. **<0.01, ***<0.001. q Percentage of disease relevant cytokines in LP, AD, and psoriasis normalised to 100%. LP lichen planus, AD atopic dermatitis.

Fig 5: Circulating CD161+CD4+ T cells of HBV cohorts express a certain pattern of cytokines and liver-homing chemokine receptors. (a, b) Representative scatter plots (a) and statistical analysis of frequencies (b) of IL-17A, IFN-? or IL-17A/IFN-? producing CD161+CD4+ T cell subsets in HC, CHB and LC groups. (c) Statistical analysis of frequencies of IL-17A/IFN-? co-producing CD161+CD4+ T cell subsets in the biopsied HBV cohort. (d–f) Representative scatter plots (d) and statistical analysis of frequencies (e, f) of CCR6, CXCR6 or CX3CR1 expressing CD161+CD4+ T cell subsets in HC, CHB and LC groups (all n = 24) (e), and in the biopsied HBV cohort (f). (g–i) Representative immunohistochemical staining (g) and quantification (h) of intrahepatic CD161+ cells (hpf, high-power field, 400× magnification) in the biopsied HBV cohort. (i) Statistical correlations between the intrahepatic CD161+ T cell number and frequencies of circulating CD161+CD4+ T cell subsets expressing CCR6, CXCR6 or CX3CR1 in the biopsied HBV cohort (*P < 0.05; **P < 0.01).