Role of myofibroblasts during normal tissue repair and excessive scarring: interest of their assessment in XXXX .

@entity32 @entity8 @entity82 @entity66 @entity177
Following injury, tissue repair process takes place involving @entity32 , granulation tissue formation and scar constitution. Granulation tissue develops from the connective tissue surrounding the damaged area and contains vessels, inflammatory cells, fibroblasts and myofibroblasts. Myofibroblasts play an important role in many tissue injuries and @entity66 . The process of normal wound repair after tissue injury follows a closely regulated sequence including the activation and the proliferation of fibroblastic cells. In pathological situations, the normal resolution stages are abrogated and the proliferation of myofibroblasts continues, inducing excessive accumulation of extracellular matrix. The differentiation of fibroblastic cells into myofibroblasts is an early event in the development of tissue @entity82 . Myofibroblastic cells express smooth muscle cytoskeletal markers (alpha-smooth muscle actin in particular) and participate actively in the production of extracellular matrix. The evaluation of myofibroblast differentiation in renal biopsies would be useful for histopathologists to appreciate the intensity of tissue injury and particularly to predict the long term outcome of some @entity8 . Immunohistochemical studies for alpha-smooth muscle actin should be made systematically in renal tissue biopsies. Myofibroblastic differentiation appears to play a significant role in the progression of @entity177 and seems to be a useful marker of progressive disease.
