Researchers at the Second Department of Surgery, Asahikawa Medical College and the Department of Surgery, Okayama University Graduate School of Medicine and Dentistry in Japan carried out a study to evaluate the cytoprotective effect of University of Wisconsin (UW) solution during cryopreservation of rat hepatocytes. Crytopreserved hepatocytes are a ready source of metabolic and synthetic functions for hepatocyte-based biological therapies, such as hepatocyte transplantation and a bioartificial liver. These therapies are promising for the treatment of patients with liver failure and for starters, the study did demonstrate that modifications in UW-solution based cryopreservation  could be a step in the right direction.

In the study, primary rat hepatocytes were isolated by two step collagenase perfusion technique and resulting hepatocytes of >85% viability assesses. These hepatocytes were cryopreservation in UW solution with 12% DMSO (Group 1), cellbanker II solution (GROUP 2), and regular DMEN medium supplemented 10% fetal bovine serum and 12% DESO (Group 3), for 24 to144 hours. After thawing the cryopreservation hepatocytes, cell viability, cell culture, ammonia clearance activity, and efficacy of adenovirus (AdLacZ) – and lentivirus (LtLacZ) - mediated E. coli LacZ gene transfer were compared among the groups. Hepatocyte viability immediately after thawing was 60% for G1, 54%, G2 and 42% for G3, respectively, compensated by the initial cell viability. Plating and ammonia clearance of hepatocytes were significantly improved in G1 hepatocytes. Efficient transduction using AdLacZ and LtLacZ was achieved in the cryopreservation hepatocytes with UW solution.