Figure 1.

Representative images of thymic stromal lymphopoietin (TSLP) expression in the skin of patients with diffuse cutaneous systemic sclerosis (dcSSc). A, Skin from a healthy control (HC) showing TSLP staining in brown with a vessel on the bottom right. Original magnification × 10. B, Higher-magnification view of the vessel in A, showing positive TSLP staining on endothelial cells. Original magnification × 20. C, Skin from a dcSSc patient showing TSLP staining in brown with positive staining on interstitial cells and on the vessels on the bottom left and upper right. Original magnification × 10. D, Higher-magnification view of the left vessel in C, showing positive staining on endothelial cells and in the perivascular area. Original magnification × 20. E and F, Scores for TSLP-positive staining of the perivascular area (E) and interstitial cells (F) in skin samples from healthy controls (n = 10) and SSc patients (n = 11). Bars show the mean ± SEM. G–K, Representative images of immunofluorescence analysis of skin samples from dcSSc patients stained for DAPI in blue and CD31 in cyan (G), stained for CD8+ cells in green, TSLP in red, and a few cells colocalizing with TSLP in yellow (arrows) (H), stained for CD4+ cells in green, TSLP in red, and a few cells colocalizing with TSLP in yellow (arrows) (I), stained for DAPI in blue, TSLP in red, and cells colocalizing with TSLP in purple (J), and stained for CD163+ cells in green, TSLP in red, and cells colocalizing with TSLP in yellow (arrows) (K). Original magnification × 60. L, TSLP-positive staining (brown) in 2 perivascular areas and in the epithelial cell layer. Original magnification × 10. M, TSLP-positive staining (brown) in the perivascular area shown in the boxed area in L. Original magnification × 20. Sections shown in L and M were incubated with rabbit anti-human polyclonal antibody. N, Staining of the area shown in H with peptide-blocked anti-TSLP control (TSLP synthetic peptide; negative staining).