CD133+ stem cell mobilization after partial hepatectomy depends on resection extent and underlying disease

Background: Bone marrow stem cells (BMSC) can participate to liver regeneration. However, conflicting results have been reported on this topic in patients undergoing liver resection. Aims: To assess the impact of liver resection extent and presence of underlying liver disease in modulating BMSC mobilization. Methods: We enrolled 29 patients undergoing liver resection of different extents, 5 surgical controls and 10 blood donors. Circulating CD133+ BMSC were measured by flow cytometry at different time-points after surgery. The hepatic commitment of mobilized BMSC was investigated by polymerase chain reaction. Liver specimens were collected during surgery for histopathological analysis. Hepatocyte growth factor and granulocyte-colony stimulating factor serum levels were measured by enzyme-linked immunosorbent assay. Results: BMSC mobilization was found in patients undergoing major liver resection, especially in the presence of underlying disease. Ductular reactions were noted in patients with chronic hepatopathy and the hepatic progenitor-like cells expressed CD133, NCAM, cytokeratin-19, and alpha-fetoprotein. Hepatocyte growth factor and granulocyte-colony stimulating factor levels increased following liver resection and the contemporaneous presence of liver disease was associated with their highest raise. Conclusions: Liver repair is mainly an endogenous process. BMSC become important in case of extensive resection, especially in the presence of underlying hepatopathy and hepatic progenitor-like cells activation. Hepatocyte growth factor and granulocyte-colony stimulating factor seem to be involved in the dynamics underlying hepatic regeneration and BMSC recruitment. (C) 2010 Editrice Gastroenterologica Italiana S.r.l. Published by Elsevier Ltd. All rights reserved.