by storm. It is perhaps the most intriguing and controversial of recent hypotheses on the
mechanism of fibrosis that injured epithelial cells, via an EMT, contribute directly to matrix
deposition and repair. Originally invoked as a source of collagen-producing cells in the
kidney, 1, 2 EMT is now thought to occur in fibrosis of the lung and, through the transition of
both hepatocytes and cholangiocytes, the liver. 3–5 This has important theoretical and
practical implications for studying fibrosis: EMT provides a potential mechanism for the rapid …