P16. WITHDRAWN P17. Free Flap as the Vascularized Foundation for Hepatic Tissue Engineering

PURPOSE: Creation of patient-specific replacement organs promises to address major shortcomings of current strategies in transplantation, namely relating to the need for life-long immunosuppression and limited donor supply. We previously described a novel approach to fabricate autologous, vascularized neo-organs in vitro. This method uses expendable microcirculatory beds (EMBs) found within free flaps that are maintained ex vivo on a perfusion bioreactor and seeded with autologous stem cells. Unlike existing tissue engineering paradigms that rely upon vascular ingrowth from the wound bed, this method starts with the intact vascular system and surrounding stromal support and builds tissue from the “inside out.” In this fashion, we address the blood supply from the time of implantation, which is a critical bottleneck in current tissue engineering strategies. Here, building upon this we developed a protocol for the differentiation of autologous adipose-derived stem cells (ASCs) into hepatocyte-like cells in vitro, for the purpose of creating a functional neo-liver. We also demonstrate that tri-cultures recapitulating fetal hepatic developmental conditions result in spontaneous organization into hepatic buds.