Hematopoietic mobilization in mice increases the presence of bone marrow–derived hepatocytes via in vivo cell fusion

✍ Scribed by Oscar Quintana-Bustamante; Alberto Alvarez-Barrientos; Alexander V. Kofman; Isabel Fabregat; Juan A. Bueren; Neil D. Theise; José C. Segovia

• Publisher: John Wiley and Sons
• Year: 2006
• Tongue: English
• Weight: 596 KB
• Volume: 43
• Category: Article
• ISSN: 0270-9139
• DOI: 10.1002/hep.21005

✦ Synopsis

The mechanisms for in vivo production of bone marrow-derived hepatocytes (BMDHs) remain largely unclear. We investigated whether granulocyte colony-stimulating factor (G-CSF)-mediated mobilization of hematopoietic cells increases the phenomenon. Recurrent liver injury in mice expressing green fluorescent protein (EGFP) in all hematopoietic-derived cells was produced by 3 months of carbon tetrachloride (CCL4) injections. Histologically, there were necrotic foci with histiocyte-rich infiltrates, but little oval cell proliferation. Subsequently, some animals were mobilized with G-CSF for 1, 2, or 3 weeks. Animals were sacrificed 1 month after growth factor treatment. BMDH percentages were lower than previously reported, though G-CSF mobilization significantly augmented BMDH production in injured livers. BMDHs originating from in vivo fusion were evaluated by transplanting female EGFP+ cells into male mice. Binucleated, EGFP+ hepatocytes with one Y chromosome, indicating fusion, were identified. In conclusion, (1) mobilization of hematopoietic cells increases BMDH production and (2) as with the FAH-null model, the first model demonstrating hematopoietic/hepatocyte fusion, recurring CCl4-induced injury has macrophage-rich infiltrates, a blunted oval cell response, and a predominantly in vivo fusion process for circulating cell engraftment into the liver. These findings open the possibility of using hematopoietic growth factors to treat nonhematopoietic degenerative diseases.