TGFB1 and fibrosis: Fibrosis is triggered by a chronic injury to the liver which is caused by a series of events that include damage to the endothelial barrier; release of a major fibrogenic cytokine TGF-b1; production of inflammatory cells and activation of collagen-producing cells; induction of reactive oxygen species; matrix activation of myofibroblasts; finally, in the absence of continuous injury, there is a reversal of fibrosis (Kisseleva and Brenner 2008).