Sharing Experience on Long-Term Survival in A Non-Arterialized Rat Liver Transplantation Model

In experimental liver transplantation, the rat model is the gold standard for investigating transplant immunology and metabolic processes; however, reconstructing the exceedingly fine hepatic artery (~0.5 mm) presents a formidable technical challenge. To circumvent this, the simplified non-arterialized rat liver transplantation (NArLT) model is widely utilized. Unfortunately, severe biliary complications-such as bile leakage and ischemic cholangitis-arising from arterial deprivation frequently restrict the long-term survival of recipients. This obstacle significantly limits research on key topics, including long-term host-graft immunocompatibility and chronic rejection. Herein, we present an optimized protocol for the NArLT model that incorporates critical technical refinements to successfully overcome these ischemic biliary injuries. Key improvements include a significantly shortened anhepatic phase, a "no-touch" biliary dissection technique, thorough biliary tract flushing, and an optimized internal biliary stenting method. After implementing this improved procedure, the recipient survival rate exceeded 94% during the 100-day observation period. Ultimately, this optimized protocol provides a highly reproducible and robust platform to investigate the mechanisms underlying long-term transplant tolerance, thereby supporting the development of novel therapeutic strategies in transplantation medicine.