TGFB1 and pulmonary fibrosis: Given the known relationship between TGF-β1 and mitochondrial ROS production, and given the known contribution of ROS to fibrogenesis, we asked whether mitochondrial clearance is altered in idiopathic pulmonary fibrosis (IPF), and whether disruption of the critical mitophagy protein, PINK1, would alter the outcomes of in vivo and in vitro models of lung fibrosis.