Cell-Based Immunomodulatory Concepts and Tolerance Protocols for Reconstructive Transplantation

Immunomodulation and tolerance induction during vascularized composite allotransplantation (VCA) represent the “Holy Grail” of the modern era of transplantation. Although lifelong immunosuppression is justifiable for life-saving solid-organ transplantation, it may not be permissible for a life-enhancing procedure such as face or extremity transplantation. Thus, the ability to reduce or completely abolish immunosuppression regimens would significantly shift the risk-benefit balance in favor of VCA. Several immunomodulatory approaches have been attempted for tolerance induction, with central and peripheral immunologic mechanisms representing the forefront of research efforts. In this chapter, we discuss relevant cell-based approaches and experimental protocols for tolerance induction in VCA, as well as the preliminary clinical use of such protocols in reconstructive transplantation.