Abstract
Reconstruction of 10mm segmental bone defects in rat by mesenchymal stem cell derived chondrogenic cells (MSC-DC)
Background
Mesenchymal stem cell derived condrogenic cells (MSC-DC) have excellent potential for healing 5 mm bone defect in rat femur.
Purpose
To evaluate the effectiveness of MSC-DC on bone healing in 10 mm segmental bone defects in rat femur.
Methods
10 millimeter bone defects were produced in rat femur and fixed with external fixator. We divided this model into four groups according to the kind of graft for bone defects. These bone defects were grafted by MSC-DC seeded on a poly (DL-lactic acid-co-glycolic acid) (PLGA) scaffold in Group A, MSC seeded on a PLGA scaffold in Group B, PLGA scaffold only in Group C, and autologus bone graft in Group D. The healing processes were monitored radiographically and studied biomechanically and histologically.
Results
All the bone defects in Group A healed radiographically with bridging callus formation at 4 weeks after the procedure, while none of Group B, C, and D had achieved bone union even at 8 weeks. Mechanical testing revealed that Group A showed approximately 40 % bending strength at 4 weeks compared with the contralateral side, and approximately 60 % at 8 weeks. In histology, Group A, maturation of bridging callus occurred from outside and enchondral ossification was prominent from inside.
Conclusion
This study showed that MSC-DC with PLGA scaffold enhances bone healing even in large bone defects.
