Expression of mesenchymal, hematopoietic, and biliary cell markers in adult rat hepatocytes after partial hepatectomy.

Background and Purpose: It has been suggested that liver regeneration can occur either by differentiated adult hepatocytes which retain the capability for several rounds of replication or by hepatic progenitor cells, depending on the number of hepatocytes lost. We sought to study the differentiation potential of hepatocytes following partial hepatectomy (PH) in rats.
Methods: Using immunohistochemistry and confocal microscopy we studied the distribution of cytokeratin 7 (CK7), CK19, vimentin, desmin, CD34, and c-kit among adult rat liver hepatocytes after PH at various times just after hepatectomy and after 8, 16, 24, 36, 48, and 60 hour and 6 and 16 days.
Results: Vimentin, c-kit, and desmin positivity were observed in regenerating hepatocytes in the early stages. Desmin and vimentin staining were also demonstrated in stellate cells. Staining enhancement in stellate cells progressed from day 3 to day 6. No liver sections were stained positive for CD34, CK19, or CK7.
Conclusion: After PH, mature hepatocytes revealed their potential to regain the markers that they do not express when they are quiescent. This result supported the plasticity and differentiation potential of adult hepatocytes during regeneration.