Hepatic stellate cells play a key role in the development of liver fibrosis that is characterized by a quantitative and qualitative changes in the composition and distribution of the extracellular matrix . Under the influence of the compounds released from damaged hepatocytes and Kupffer cells Browicz - , platelets , white blood cells and endothelial cells , there is a transition ( activation ) stellate cells quiescent cells myofibroblast phenotype .