Hand transplantation: pertinent data and future outlook.

Transplantation of composite tissue allografts, such as a hand, offers immense potential in reconstructive surgery. Review of current replantation literature suggests the prospect for significant functional return following hand transplant, provided appropriate patient is selected and allograft rejection is prevented. Experimental studies of limb transplantation in rodents have demonstrated the efficacy of combination therapy using multiple immunosuppressants. However, long-term survival of limb allografts could not be achieved in large animal models without significant drug toxicity. Given the potential for organ failure, opportunistic infection, and malignancy resulting from long-term immunosuppression, the risk-benefit ratio for hand transplant must be carefully weighed. Our laboratory has been able to achieve allograft survival with minimum immunosuppression by MHC matching or donor antigen exposure prior to immune maturity in the swine. Future transplantation of composite tissue allografts, therefore, may depend upon such modalities to induce host tolerance without long-term immunosuppression.