AIM: To investigate the use of Daclizumab (Dmab) as an immunosuppressive agent in an experimental model of hepatocyte xenotransplantation (XenoTx) in rats with fulminant hepatic failure (FHF).METHODS: Two white male New Zealand rabbits were used as donors and 68 Wistar rats as recipients.FHF was induced by intravenous application of dimethylnitrosamine (DMNA). The isolated hepatocytes of the rabbits were xenotransplanted into the spleen of the rats 24 h after FHF induction. Group A (n = 13): no treatment; Group B (n = 14): FHF and XenoTx; Group C (n = 14): FHF and XenoTx and cyclosporin (CsA); Group D (n = 14): FHF and XenoTx and Dmab; Group E (n =13): FHF and XenoTx and CsA and Dmab. The rats were followed for 15 d.RESULTS: Statistical analysis showed better survival among groups D (92.86%) and E (76.92%) compared to group A (all rats died after 72 h), group B (28.57%)or group C (71.43%), although the differences were not statistically significant. Biochemical evaluation of the liver enzymes and histology confirmed satisfactory function and engraftment, respectively.CONCLUSION: This experimental model has shown the safe, effective and beneficial use of Dmab in a xenotransplantation model of rabbit hepatocytes in rats.