Composite Tissue Transplantation: A Rapidly Advancing Field

Abstract

Composite tissue allotransplantation (CTA) is emerging as a potential treatment for complex tissue defects. It is currently being performed with increasing frequency in the clinic. The feasibility of the procedure has been confirmed through 30 hand transplantation, 3 facial reconstructions, and vascularized knee, esophageal, and tracheal allografts. A major drawback for CTA is the requirement for lifelong immunosuppression. The toxicity of these agents has limited the widespread application of CTA. Methods to reduce or eliminate the requirement for immunosuppression and promote CTA acceptance would represent a significant step forward in the field. Multiple studies suggest that mixed chimerism established by bone marrow transplantation promotes tolerance resulting in allograft acceptance. This overview focuses on the history and the exponentially expanding applications of the new frontier in CTA transplantation: immunology associated with CTA; preclinical animal models of CTA; clinical experience with CTA; and advances in mixed chimerism-induced tolerance in CTA. Additionally, some important hurdles that must be overcome in using bone marrow chimerism to induce tolerance to CTA are also discussed.

A Survey of North American Hand Surgeons on Their Current Attitudes Toward Hand Transplantation

“…com). [3][4][5][6][7][8][9][10][11][12] Although solid organ transplantation is widely accepted in the medical community as the best treatment of end-stage organ failure, there remain strong differences in opinion concerning the utility of CTA for hand transplantation. [13][14][15][16][17][18][19] The proponents of hand transplantation see it as an opportunity to truly restore function to those who have lost their hands.…”

Microsurgery of the Upper Extremity

“…Current research is focused on achieving tolerance and reducing or eliminating immunosuppressive therapy. 107,108 Dr. Earl Peacock 109,110 performed the first CTA using flexor tendons to treat end-stage tendon incarceration. In 1967, the first hand transplant was performed in Ecuador and failed after 3 weeks, from acute rejection.…”

Translational Animal Models for Regenerative Medicine Research

“…The scope is primarily limited to models in which autologous, allogeneic or xenogeneic cells and/or engineered composite tissues or scaffolds are employed for tissue repair or regeneration. It minimally discusses models employed to evaluate whole intact organ transplants or composite allografts (e.g., hand and face transplants), as these have been reviewed elsewhere [1,2].…”