Vascular study of decellularized porcine long bones: Characterization of a tissue engineering model

• Published in: Bone (New York, N.Y.) N.Y.), 2024-05, Vol.182, p.117073-117073, Article 117073
• Main Authors: Evrard, R., Manon, J., Rafferty, C., Fieve, L., Cornu, O., Kirchgesner, T., Lecouvet, F.E., Schubert, T., Lengele, B.
• Format: Article
• Language: English
• Subjects: Animals; Arteries; Bone and Bones; Bone imaging; Collagen; Decellularization by perfusion; Extracellular Matrix; Massive bone allograft; Porcine bone; Swine; Tissue Engineering - methods; Tissue Scaffolds - chemistry; Vascularization; von Willebrand Factor - analysis
• ISSN: 8756-3282; 1873-2763
• DOI: 10.1016/j.bone.2024.117073

Massive bone allografts enable the reconstruction of critical bone defects in numerous conditions (e.g. tumoral, infection or trauma). Unfortunately, their biological integration remains insufficient and the reconstruction may suffer from several postoperative complications. Perfusion-decellularization emerges as a tissue engineering potential solution to enhance osseointegration. Therefore, an intrinsic vascular study of this novel tissue engineering tool becomes essential to understand its efficacy and applicability. 32 porcine long bones (humeri and femurs) were used to assess the quality of their vascular network prior and after undergoing a perfusion-decellularization protocol. 12 paired bones were used to assess the vascular matrix prior (N = 6) and after our protocol (N = 6) by immunohistochemistry. Collagen IV, Von Willebrand factor and CD31 were targeted then quantified. The medullary macroscopic vascular network was evaluated with 12 bones: 6 were decellularized and the other 6 were, as control, not treated. All 12 underwent a contrast-agent injection through the nutrient artery prior an angio CT-scan acquisition. The images were processed and the length of medullary vessels filled with contrast agent were measured on angiographic cT images obtained in control and decellularized bones by 4 independent observers to evaluate the vascular network preservation. The microscopic cortical vascular network was evaluated on 8 bones: 4 control and 4 decellularized. After injection of gelatinous fluorochrome mixture (calcein green), non-decalcified fluoroscopic microscopy was performed in order to assess the perfusion quality of cortical vascular lacunae. The continuity of the microscopic vascular network was assessed with Collagen IV immunohistochemistry (p-value = 0.805) while the decellularization quality was observed through CD31 and Von Willebrand factor immunohistochemistry (p-values