Helal TESA, Ehsan NA, Radwan NA, Abdelsameea E. Relationship between hepatic progenitor cells and stellate cells in chronic hepatitis C genotype 4. APMIS 2018; 126: 14-20.Hepatitis C virus (HCV) infection represents a major health problem in many areas of the world, especially Egypt. Hepatic progenitor cells (HPCs) and hepatic stellate cells (HSCs) have been implicated in fibrosis progression in chronic HCV. The aim of this study was to investigate the role of HPCs and HSCs in chronic HCV infection and the relationship between both cell types. This retrospective study was conducted on 100 chronic HCV patients. Immunohistochemistry was performed on liver tissue sections for cytokeratin 19 (progenitor cell markers), smooth muscle actin (stellate cell markers), matrix metalloproteinase-9 (MMP-9), and transforming growth factor beta (TGF-ß). The necroinflammatory activity was significantly related to the number of isolated HPCs and TGF-ß expression (p = 0.003 and p = 0.001 respectively). Advanced stages of fibrosis showed significantly increase number of HPCs (p = 0.001), higher ratio of HSCs (p = 0.004), more expression of TGF-ß (p = 0.001) and MMP-9 (p = 0.001). There was a significant direct correlation between immunoexpression of HPCs and HSCs for isolated cells (r = 0.569, p = 0.001) and ductular reaction (r = 0.519, p = 0.001). Hepatic progenitor cells and stellate cells play a significant role in the development and progression of fibrosis in chronic HCV. More interestingly, the significant direct correlation between HPCs and HSCs suggests a synergistic interrelation.