COL1A1 and systemic sclerosis: We showed that the main markers of fibrosis, namely αSMA and COL1A1, as well as the MMP1/TIMP1 ratio, were expressed at similar levels in Tβ-Fb and SSc-Fb, indicating a close myofibroblastic signature and the relevance of the Tβ-Fb model for mimicking SSc-Fb.