Objective: To study the vascularization of the composite of bio-derived bone and marrow stromal stem cells (MSCs) in repairing goat tibial shaft defect.
Methods: Bio-derived bone was processed as scaffold material. MSCs were harvested and cultured in vitro. The multiplied and induced cells were seeded onto the scaffold to construct tissue engineered bone. A 20 mm segmental bone defect in length was made in the middle of the tibia shaft in 20 mature goats and fixed with plate. The right tibia defect was repaired by tissue engineered bone (experimental side), and the left one was repaired by scaffold material (control side). The vascularization and osteogenesis of the implants were evaluated by transparent thick slide, image analysis of the vessels, and histology with Chinese ink perfusion 2, 4, 6, and 8 weeks after operation.
Results: More new vessels were found in control side than in experimental side 2 and 4 weeks after implantation (P<0.05). After 8 weeks, there was no significant difference in number of vessels between two sides (P>0.05), and the implants were vascularized completely. New bone tissue was formed gradually as the time and the scaffold material degraded quickly after 6 and 8 weeks in the experimental side. However, no new bone tissue was formed and the scaffold degraded slowly in control side 8 weeks after operation.
Conclusion: Bio-derived bone has good quality of vascularization. The ability of tissue-engineered bone to repair bone defect is better than that of bio-derived bone alone.