[1] St James Univ Hosp, HPB & Transplant Unit, Leeds LS9 7TF, W Yorkshire, England
[2] Univ Roma Tor Vergata, Osped S Eugenio, Transplant & Gen Surg Unit, Rome, Italy
[3] Wake Forest Inst Regenerat Med, Winston Salem, NC USA
[4] Univ Oxford, Dept Surg, Nuffield Univ Hosp, Oxford, England