Bone vascularized composite allotransplantation model in swine tibial defect

• Verfasst von: Kotsougiani-Fischer, Dimitra [VerfasserIn]
• Titel: Bone vascularized composite allotransplantation model in swine tibial defect
• Titelzusatz: evaluation of surgical angiogenesis and transplant viability
• Verf.angabe: Dimitra Kotsougiani MD, Caroline A. Hundepool MD, PhD, Liselotte F. Bulstra MSc, Patricia F. Friedrich AAS, Alexander Y. Shin MD, Allen T. Bishop MD
• Jahr: 2019
• Jahr des Originals: 2018
• Umfang: 7 S.
• Teil: volume:39
• Teil: year:2019
• Teil: number:2
• Teil: pages:160-166
• Teil: extent:7
• Fussnoten: First published: 05 March 2018 ; Gesehen am 05.12.2019
• Titel Quelle: Enthalten in: Microsurgery
• Ort Quelle: New York, NY [u.a.] : Wiley-Liss, 1979
• Jahr Quelle: 2019
• Band/Heft Quelle: 39(2019), 2, Seite 160-166
• ISSN Quelle: 1098-2752
• DOI: doi:10.1002/micr.30310
• Datenträger: Online-Ressource
• Sprache: eng
• K10plus-PPN: 1677555203

Abstract

Introduction In prior small animal studies, we maintained vascularized bone allotransplant viability without long-term immunotherapy. Instead, an autogenous neoangiogenic circulation is created from implanted vessels, sufficient to maintain bone viability with only 2 weeks immunosupression. Blood flow is maintained despite rejection of the allogeneic vascular pedicle thereafter. We have previously described a large animal (swine) pre-clinical model, reconstructing tibial defects with vascularized tibial allotransplants. In this manuscript, autologous angiogenesis is evaluated in this model and correlated with bone viability. Materials and methods Allogeneic tibial segments were transplanted across a major swine leukocyte antigen mismatch. Microvascular repair of the bone VCA pedicle was combined with intraosseous implantation of an autogenous arteriovenous (AV) bundle. The bundle was ligated in group 1 (n = 4), and allowed to perfuse in group 2 (n = 4). Three-drug immunotherapy was given for 2 weeks. At 16 weeks micro-CT angiography quantified neoangiogenic vessel volume. Bone viability, rejection grade, and bone healing were analyzed. Results A substantial neoangiogenic circulation developed from the implanted AV-bundle in group 2, with vessel density superior to ligated AV-bundle controls (0.11 ± 0.05 vs. 0.01 ± 0.01, P = .029). Bone allotransplant viability was also significantly enhanced by neoangiogenesis (78.7 ± 4.4% vs. 27.7 ± 5.8%, P = .028) with higher bone healing scores (21.4 ± 2.9 vs. 12.5 ± 3.7, P = .029). Ligated control tibias demonstrated disorganized bone morphology and higher local inflammation (P = .143). Conclusion Implantation of autogenous AV bundles into vascularized bone allotransplants resulted in the rapid formation of a neoangiogenic autogenous blood supply in a swine tibia model that maintained bone viability, improved bone healing, and minimized rejection.