S100A4 and interstitial lung disease: Another important result of our in vitro study is the significant over-expression and over-production of fibroblast/myofibroblast phenotype markers (S100A4 and αSMA) that seems more evident in fibrocytes isolated from Scl70+ILD+ patients compared to fibrocytes isolated from Scl70−ILD− patients, as well as from HSs.