title: Chronic Rejection in Human Vascularized Composite Allotransplantation (Hand and Face Recipients): An Update.
abstract: Vascularized composite tissue allografts (VCA) have become a viable option to restore severely damaged parts of the body that cannot be repaired with conventional surgical techniques. Acute rejection develops frequently in the early postgraft period both in human and experimental VCA, but the possibility of human VCA to undergo chronic rejection (CR) remained initially unknown. The experience gained over the years shows that, similar to solid organ transplants (SOT), human VCA can also develop CR. Chronic rejection is clinically mostly apparent on the skin and targets preferentially skin and deep vessels, leading, as in SOT, to graft vasculopathy and often to graft loss. Dermal sclerosis and adnexal atrophy are additional features of CR. The pathogenetic immune mechanisms involved (cell-mediated versus humoral) remain incompletely known. The changes of CR can be detected with skin and deep tissue biopsies. Modern in vivo imaging tools can detect vascular narrowing and have the advantage of being noninvasive. However, the diagnosis and treatment of CR remain challenging, as several important questions remain to be answered: a more accurate definition of CR in VCA is needed to establish criteria allowing an accurate and early diagnosis. The pathogenetic mechanisms of CR need to be better understood to allow more efficacious treatment. Favoring/triggering factors of CR need to be better known so that they can be avoided. As in SOT, there is a need for efficient tolerance-inducing protocols that will favor graft acceptance and (ideally) circumvent the necessity of lifelong immunosuppression.
authors.affiliation: 1 Departments of Dermatology and Pathology, Edouard Herriot Hospital Group, Lyon, France. 2 Department of Surgery, University of Cagliari, Cagliari, Italy. 3 Department of Transplantation, Nephrology and Clinical Immunology, Edouard Herriot Hospital, Lyon, France. 4 Department of Hand and Arm Surgery, Orthopedic Polyclinic of Lyon, France. 5 Department of Maxillofacial Surgery, University Hospital Nord, Amiens, France.
authors.forename: Jean
authors.initials: J
authors.lastname: Kanitakis
authors.forename: Palmina
authors.initials: P
authors.lastname: Petruzzo
authors.forename: Lionel
authors.initials: L
authors.lastname: Badet
authors.forename: Aram
authors.initials: A
authors.lastname: Gazarian
authors.forename: Olivier
authors.initials: O
authors.lastname: Thaunat
authors.forename: Sylvie
authors.initials: S
authors.lastname: Testelin
authors.forename: Bernard
authors.initials: B
authors.lastname: Devauchelle
authors.forename: Jean-Michel
authors.initials: JM
authors.lastname: Dubernard
authors.forename: Emmanuel
authors.initials: E
authors.lastname: Morelon
mesh_terms: D002908:Chronic Disease; D006084:Graft Rejection / Q000175:diagnosis / Q000209:etiology* / Q000628:therapy; D006801:Humans; D063986:Vascularized Composite Allotransplantation / Q000009:adverse effects*