Biological Safety and Efficacy of the Novel Preservation Solution Ecosol in a Rat Liver Transplantation Model

Static cold storage remains the most widely used method for organ preservation in transplantation. Over time, preservation solutions have undergone continuous optimization. Ecosol is a novel extracellular-type, colloid-based preservation solution. In this study, we evaluated the safety and efficacy of Ecosol in comparison to the gold standard University of Wisconsin (UW) solution using both allogeneic and syngeneic rat orthotopic liver transplantation models. Liver function parameters were assessed and compared to baseline values of the respective rat strains. In the syngeneic setting, alanine transaminase (ALT) levels were significantly higher in the UW group than in the Ecosol group on day 1 post-transplantation (<i>p</i> < 0.05). Lactate dehydrogenase (LDH) levels were significantly elevated in the UW group compared to Ecosol in both allogeneic and syngeneic models on day 1 (<i>p</i> < 0.001). Gamma-glutamyl transferase (GGT) and total bilirubin were also significantly higher in the UW syngeneic group on day 1 (<i>p</i> < 0.05). In the allogeneic setting, aspartate aminotransferase (AST) and ALT levels were significantly elevated in both the UW (<i>p</i> < 0.0001) and Ecosol (<i>p</i> < 0.0001 and <i>p</i> < 0.001, respectively) groups on day 1 compared to the baseline values of Brown Norway (BN) rats. On day 7, these elevations persisted in the UW group, whereas no significant differences were observed in the Ecosol group compared to the baseline BN values (UW vs. Ecosol: <i>p</i> < 0.0001). In syngeneic transplants, AST and ALT levels were significantly elevated in both groups on day 1 compared to the baseline values of Lewis rats (<i>p</i> < 0.0001). By day 7, AST levels remained significantly elevated in the UW group, while Ecosol showed no significant difference from baseline (<i>p</i> < 0.0001). Organ viability, assessed via non-invasive imaging after 8 h of cold storage, was improved with Ecosol. Overall, Ecosol demonstrated biological safety and non-inferiority to the UW solution for liver preservation in a rat orthotopic liver transplantation model.