To observe the repairing effect of bone marrow mesenchymal stem cells (BMSCs) transfected by vascular endothelial growth factor (VEGF) gene on non-traumatic osteonecrosis of femoral head following implantation into the necrotic area.METHODS:
BMSCs were in vitro isolated, culture, determined, and transfected with PcDNA3/VEGF165 plasmid; thereafter, the BMSCs were cultured with recombinant heterogenous bone. Femoral head necrosis in 24 rabbits was induced with liquid nitrogen. In the treatment group, rabbits were implanted with VEGF gene-transfected BMSCs on the left defected side; while in the control group, rabbits were implanted with BMSCs on the right defected side. X-ray examination, histopathological evaluation, femoral bone density analysis, and mineral matter content measurement were conducted.RESULTS:
① X-ray examination indicated that bone trabecula structure and new bone formation were observed in the treatment group in defected area after 6 weeks; however, central density was low and marginal density was high in the control group. After 12 weeks, morphology of femoral head was regular and density was uniform in the treatment group, while a low-density band in capsular shape was observed in the control group. ② There were significant difference in bone density and mineral matter content between the two groups at 6 and 12 weeks after implantation (P < 0.01). ③ Numbers of osteocytes and blood capillary in the treatment were higher than control group after 6 weeks; in addition, after 12 weeks, nascent osseous tissue reached cartilage in the treatment group, and pieces of implanted bone remained in the control group.CONCLUSION:
BMSCs transfected by VEGF gene have a strong activity of osteoinduction, so BMSCs implantation can effectively repair non-traumatic osteonecrosis of femoral head in an early stage.