More importantly, TGF-β1 protein is specifically detected by immunohistochemical staining in areas of fibrosis.448 A similar pathophysiologic effect of increased levels of TGF-β occur in induced animal models for hepatic fibrosis.449 In a conditional transgenic mouse model with tetracycline-regulated expression of TGF-β1 in liver, fibrosis progressed to an intermediate state during the upregulation of TGF-β1 expression.450 Furthermore, the fibrogenic process can be attenuated simply by blockade of TGF-β signaling.451. This evidence concerns the gene TGFB1 and Hepatic fibrosis.