TGFB1 and pulmonary fibrosis: In the doxycycline-inducible Clara cell (CC10)-promoter driven model of TGF-β-induced lung fibrosis, addition of doxycycline to the water of animals leads to release of the tetracycline-controlled transcriptional suppressor allowing the reverse tetracycline transactivator to bind to the transgene (TGF-β) and promote its acute expression even 12 h after treatment with doxycycline (74).