Slide Session : OS-GAS-09 ; Gastroenterology : Circulating Bone Marrow-Derived Stem Cells in Pa-tients with Chronic Hepatitis C: Relation to Hepatic Progenitor Cells and Hepatocyte Proliferation = Slide Session : OS-GAS-09 ; Gastroenterology : Circulating Bone Marrow-Derived Stem Cells in Pa-tients with Chronic Hepatitis C: Relation to Hepatic Progenitor Cells and Hepatocyte Proliferation

다국어 초록 (Multilingual Abstract)

Background: Bone marrow-derived stem cells (BMSCs) are pluripotent cells that can be mobilized into circulation and recruited to sites of inflammation to promote tissue repair. The present work was designed to study circulating hematopoietic stem cells (HSCs) and mesenchymal stem cells (MSCs) and serum stem cell factor (SCF) levels in patients with chronic hepatitis C (CHC) in relation to hepatic progenitor cells (HPCs) and hepatocyte proliferation. Methods: Thirty patients with CHC and 15 healthy subjects were included in the study. The HSCs and MSCs in blood samples were identified as CD34+CD45+CD117+ and CD34-CD45-CD106+ cells respectively using flow cytometry. Serum SCF levels were measured using enzyme linked immunosorbant assay kit. Liver biopsies were examined to assess METAVIR histological activity grade and fibrosis stage. Immunohistochemical staining was done using monoclonal antibodies against cytokeratin (CK)7 for HPCs, Ki-67 as proliferation marker and alpha-smooth muscle actin for activated hepatic stellate cells (HpSCs). Results: Patients with CHC showed significant increases in the percentages of HSCs and MSCs in peripheral blood and serum SCF levels compared with healthy subjects (P < 0.05). Numerous CK7+ HPCs were detected mostly lining bile ductules in the portal tracts. Hepatocyte proliferative activity was directly correlated with HPC expansion. The percentages of circulating HSCs and MSCs showed positive correlation with serum SCF levels and inverse correlations with HPC expansion, hepatocyte proliferative activity, histological activity grade, fibrosis stage and intensity of activated HpSCs (P < 0.05). Conclusions: CHC is associated with mobilization of BMSCs into the circulation in parallel with an increased SCF production, particularly when HPC activation and hepatocyte proliferative activity are impaired. Although mobilized BMSCs are not sufficient for hepatic repopulation, they may play a role in limiting HCV-induced liver damage.