AIM To evaluate the therapeutic effects of bone marrowderived CD11b+CD14+ monocytes in a murine model of chronic liver damage. METHODS Chronic liver damage was induced in C57BL/6 mice by administration of carbon tetrachloride and ethanol for 6 mo. Bone marrow-derived monocytes isolated by immunomagnetic separation were used for therapy. The cell transplantation effects were evaluated by morphometry,biochemical assessment,immunohistochemistry and enzyme-linked immunosorbent assay. RESULTS CD11b+CD14+ monocyte therapy significantly reduced liver fibrosis and increased hepatic glutathione levels. Levels of pro-inflammatory cytokines,including tumor necrosis factor-α,interleukin(IL)-6 and IL-1β,in addition to pro-fibrotic factors,such as IL-13,transforming growth factor-β1 and tissue inhibitor of metalloproteinase-1 also decreased,while IL-10 and matrix metalloproteinase-9 increased in the monocytetreated group. CD11b+CD14+ monocyte transplantation caused significant changes in the hepatic expression of α-smooth muscle actin and osteopontin. CONCLUSION Monocyte therapy is capable of bringing about improvement of liver fibrosis by reducing oxidative stress and inflammation,as well as increasing antifibrogenic factors. AIM To evaluate the therapeutic effects of bone marrow derived CD11b + CD14 + monocytes in a murine model of chronic liver damage. METHODS Chronic liver damage was induced in C57BL / 6 mice by administration of carbon tetrachloride and ethanol for 6 months. Bone marrow-derived monocytes isolated by immunomagnetic separation were used for therapy. The cell transplantation effects were evaluated by morphometry, biochemical assessment, immunohistochemistry and enzyme-linked immunosorbent assay. RESULTS CD11b + CD14 + monocyte therapy significantly reduced liver fibrosis and increased hepatic glutathione levels. Levels of pro- inflammatory cytokines , including tumor necrosis factor-α, interleukin (IL) -6 and IL-1β, in addition to pro-fibrotic factors, such as IL-13, transforming growth factor-β1 and tissue inhibitor of metalloproteinase- -10 and matrix metalloproteinase-9 increased in the monocytetreated group. CD11b + CD14 + monocyte transplantation caused significant changes in the hepa tic expression of α-smooth muscle actin and osteopontin. CONCLUSION Monocyte therapy is capable of bringing about improving of liver fibrosis by reducing oxidative stress and inflammation, as well as increasing antifibrogenic factors.