Figure 4. Representative immunofluorescence images and immunoblotting showing the effect of RNAi-mediated Smad2/3/4 knockdown on αSMA. Control human corneal fibroblast cultures (–TGFβ) showed no αSMA staining (A) or protein levels (F). Cultures treated with TGFβ1 (5 ng/ml) showed robust αSMA staining (B) and protein levels (F). The knockdown of Smad2 (C, F)/Smad3 (D, F)/Smad4 (E, F) markedly blocked TGFβ-evoked increase in αSMA.