Fig 1: Clonal landscape within disease groups.(A) Total cell counts of the top 10 T cell receptor (TCR) clonotypes summarized for each condition: HC (n = 4), trunk AD (n = 5), head/neck AD (n = 5) and DAHND (n = 6); each dot represents a single individual; data are presented as median with IQR. B Absolute numbers of cells harboring the top 10 TCR clonotypes within each donor as distributed across lymphocyte clusters; data are presented as median with IQR. C Venn diagram of genes differentially up- or downregulated between the top 10 T cell oligoclones and the polyclonal T cell infiltrate, as calculated for each disease group, with expression levels of selected markers within the top 10 expanded clones (oligoclonal) and all other TCR+ cells (polyclonal). Differential gene expression was defined as log2 fold change >∣ ± 0.25∣ and adjusted p < 0.05. Selected genes are presented in a dot plot; coloring denotes expression levels within each group (red is high). D Expression of CD8A, CD8B, and CD4 by each of the top 10 expanded T cell clones per sample; coloring denotes expression levels (red is high). E, F Representative pictures of multicolor immunofluorescence stainings for CD8, CD129 (IL9R), CD314 (KLRK1), with triple-positive cells appearing in white (arrows), as well as absolute cell counts per mm of epidermis across conditions: HC (n = 3), trunk AD (n = 4), head/neck AD (n = 5) and DAHND (n = 3); each dot represents a single donor; data are presented as median with IQR. G Location of top 10 expanded T cell clones in UMAP plots of indicated disease groups. H Feature plots of T cell cytokine gene expression in each disease group. Intensity of expression levels for each cell is color-coded (red) and overlaid onto UMAP plots. I Gene expression dot plots displaying average and frequency of expression of selected markers for each disease group. Circle size represents the percentage of cells expressing the specific marker within a cluster. Coloring denotes expression levels within each group (red is high). J, K Representative pictures of multicolor immunofluorescence stainings for CD8, CD129 (IL9R), and IL-22, with triple-positive cells appearing in white (arrows), as well as quantification of absolute cell numbers per mm of epidermis across conditions: HC (n = 3), trunk AD (n = 4), head/neck AD (n = 5) and DAHND (n = 3); each dot represents a single donor; data are presented as median with IQR. Statistical significance in this figure was calculated using a Kruskal–Wallis test for multiple comparisons followed by a Dunn’s post hoc test.