Fig. 1
Activation of STAT3 signaling in fibrotic SSc skin. a–d Evaluation of STAT3 signaling in human samples: a Representative images and b quantitative analysis of immunofluorescence staining for P-STAT3 (left) and total STAT3 (right) co-stained with the vimentin (fibroblast marker) and DAPI (staining of nuclei) shown at 200-fold and 1000-fold magnification (n = 12 for SSc and n = 10 for healthy skin). c Western blots and d quantification of the levels of P-STAT3 and total STAT3 in human dermal fibroblasts from 13 SSc patients and 12 healthy individuals. e–g Evaluation of STAT3 signaling in the mouse model of bleomycin-induced skin fibrosis: e Representative images of immunofluorescence stainings (200-fold and 1000-fold magnification) showing P-STAT3 (left) and total STAT3 (right) along with f quantification and g confirmation by western blot analyses in the skin of mice injected with NaCl or bleomycin (n ≥ 6 for each group). h–j Evaluation of STAT3 signaling in the mouse model of TBRact-induced fibrosis: h Western blot and i, j immunofluorescence analyses of P-STAT3 expression in the skin of mice injected with TBRact. N ≥ 6 for each group with two or three technical replicates for all experiments. Expected band size for P-STAT3 and STAT3 are 79 kDa (lower faint band) and 86 kDa (higher intense band) and the ladder represents 100 kDa. Beta-actin expected molecular weight/size is 42 kDa. Horizontal scale bar, 100 μm. Results are shown as median ± interquartile range (IQR). Significance was determined by Mann–Whitney test, as compared to healthy volunteers or with non-fibrotic control mice, respectively. *P < 0.05; **P < 0.01, ***P < 0.001
