Composite tissue allotransplantation: development of a preclinical model in nonhuman primates.
BACKGROUND
Composite tissue allotransplantation (CTA) has been recently introduced as a potential treatment for tissue loss secondary to burns, injuries, or resections. However, the optimal strategies to prevent CTA rejection remain undefined. Presently, no CTA model exists to evaluate human-specific immunosuppressants or the relative immunogenicity of all CTA tissues.


METHODS
We established a NHP CTA model utilizing a sensate osteomyocutaneous radial forearm flap that avoids functional impairment even in the case of graft loss. The model was evaluated in19 monkeys that underwent auto- or allotransplantation, with or without subtherapeutic immunosuppression to temporarily characterize rejection.


RESULTS
Autografts showed no evidence of rejection. Nonimmunosuppressed allografts were rapidly rejected showing a perivenular T-cell infiltrate. This was associated with subsequent alloantibody formation and led to graft thrombosis without prominent dermal infiltration. Subtherapeutically immunosuppressed animals also developed alloantibody and rejected in a delayed fashion exhibiting a marked dermal lymphocytic infiltrate similar in magnitude and distribution to previously reported human cases.


CONCLUSIONS
Our NHP model for CTA is well tolerated by NHPs, results in allosensitization, is responsive to immunosuppression, allows for the evaluation of CTA histology and can be used for the systematic preclinical evaluation of therapeutic maneuvers to improve allograft survival.
Cendales
Linda C
LC
Orthopedic Section, Office of the Clinical Director, National Institute of Arthritis and Musculoskeletal and Skin Diseases, National Institutes of Health, Bethesda, MD 20892-1102, USA. cendalesl@mail.nih.gov
Xu
He
H
Bacher
John
J
Eckhaus
Michael A
MA
Kleiner
David E
DE
Kirk
Allan D
AD
D000818:Animals; D001706:Biopsy; D005542:Forearm / Q000601:surgery*; D006084:Graft Rejection / Q000517:prevention & control*; D007166:Immunosuppressive Agents / Q000627:therapeutic use; D008252:Macaca fascicularis; D008775:Methylprednisolone / Q000627:therapeutic use; D023421:Models, Animal; D018482:Muscle, Skeletal / Q000637:transplantation*; D009173:Mycophenolic Acid / Q000031:analogs & derivatives / Q000627:therapeutic use; D011884:Radius / Q000637:transplantation*; D013524:Surgical Flaps; D016559:Tacrolimus / Q000627:therapeutic use; D013710:Tendons / Q000637:transplantation*; D014184:Transplantation, Homologous / Q000276:immunology / Q000379:methods*
D007166:Immunosuppressive Agents; D009173:Mycophenolic Acid; D016559:Tacrolimus; D008775:Methylprednisolone