Intragraft Chimerism Following Composite Tissue Allograft

Until now, more than 35 hand transplants have been performed in humans and have generated much public interest. Cell traffic from the recipient into the graft, so-called intragraft chimerism, appears to play a major role in graft acceptance and graft rejection. Little is known about cell migration following extremity allografts. In this review, recent experimental studies are presented for intragraft chimerism of the extremity allograft. Technical tools for detecting recipient cells in the graft were: (1) immunohistochemistry, (2) karyotyping, (3) fluorescent in situ hybridization, (4) polymerase chain reaction, and (5) transgenic animals. This study demonstrates that recipient-derived cells gradually repopulate into grafted skin, bone tissues, bone marrow, and endothelial cells, but muscle, periosteum, and cartilage tissues retain donor cell origin.