The resectable liver volume is strictly limited and this reduces the number of patients who may be treated. Recently, “tissue/organ decellularization”, a new approach in bioengineering, has been investigated for its ability to produce a native organ scaffold by removing all the viable cells. Such a scaffold may support the repair of damaged or injured tissue. The purpose of this study was to evaluate the potential contribution of liver scaffolds to hepatic regeneration after hepatectomy. We sutured the partial liver scaffolds onto the surfaces of partially hepatectomized porcine livers and assessed their therapeutic potential by immune histological analysis at various time points. Animals were sacrificed after surgery and the implanted scaffolds were evaluated for the infiltration of various types of cells. Immune histochemical study showed that blood vessel-like structures, covered with CD31 positive endothelial cells and ALB positive cells, were present in all parts of the scaffolds at days 10 and 28. Blood inflow was observed in some of these ductal structures. More interestingly, CK19 and EpCAM positive cells appeared at day 10. These results suggest that the implantation of a decellularized organ scaffold could promote structural reorganization after liver resection.

A feasible large animal model to evaluate regenerative medicine techniques is vital for developing clinical applications. One such appropriate model could be to use retrorsine (RS) together with partial hepatectomy (PH). Here, we have developed the first porcine model using RS and PH. RS or saline control was administered intraperitoneally to Göttingen miniature pigs twice, two weeks apart. Four weeks after the second dose, animals underwent PH. Initially, we tested different doses of RS and resection of different amounts of liver, and selected 50 mg/kg RS with 60% hepatectomy as our model for further testing. Treated animals were sacrificed 3, 10, 17 or 28 days after PH. Blood samples and resected liver were collected. Serum and liver RS content was determined by Liquid Chromatograph-tandem Mass Spectrometer. Blood analyses demonstrated liver dysfunction after PH. Liver regeneration was significantly inhibited 10 and 17 days after PH in RS-treated animals, to the extent of 20%. Histological examination indicated hepatic injury and regenerative responses after PH. Immunohistochemical staining demonstrated accumulation of Cyclin D1 and suppression of Ki-67 and PCNA in RS-treated animals. We report the development of the first large animal model of sustained liver injury with suppression of hepatic regeneration.