In a rat liver fibrosis model, bleomycin-induced lung fibrosis mouse model, and a rat unilateral ureteral obstruction (UUO) model for renal fibrosis, adenoviral or doxycycline-induced overexpression of Smad 7 blocked TGFβ signaling and suppressed fibrosis (Nakao et al., 1999; Dooley et al., 2003; Lan et al., 2003). Here, TGFB1 is linked to pulmonary fibrosis.