Immunodetection and quantification of tTG by Western blotting. Control, Scr-RNAi and tTG-RNAi, were groups of HSC exposed to Polybrene, GFP-RNAi-Lentivirus, and tTG-RNAi-Lentivirus, respectively, (a) A representative result of western blotting, (b) Graphical representation of relative optical density for the left image. *, P<0.01 and **, P<0.05.