CCN2 and systemic sclerosis: We compared features of phenotypic VSMC-myofibroblast conversion of MSCs from healthy controls (H-MSCs) and SSc-MSCs in response to key mediators including connective tissue growth factor (CTGF), basic fibroblast growth factor (b-FGF), platelet derived growth factor-BB (PDGF-BB) and transforming growth factor-β1 (TGF-β1).