Autologous bone marrow mesenchymal stem cells and related chemokines in fracture microenvironment / 中国组织工程研究

ABSTRACT

BACKGROUND: The oriented migration of bone marrow mesenchymal stem cells may depend on the interaction between local chemotactic factors and cellsurface receptors. However, which chemotactic factors may mediate the oriented migration of bone marrow mesenchymal stem cells towards the fracture site remains unclear. OBJECTIVE: To tag autologous bone marrow mesenchymal stem cells, evaluate its role in bone healing, and detect the highly expressed factors associated with migration of bone marrow mesenchymal stem cells in the microenvironment. METHODS: The fluorescence/chimeric C57BL/6 mouse models were established, then left shankbone fracture models were also produced. The percentages of green fluorescent protein positive cells to al cells at the fracture site and the percentage of osteoblasts differentiated from bone marrow mesenchymal stem cells to al the osteoblasts were detected at different time points. The role of bone marrow mesenchymal stem cells in the fracture repairing was evaluated. The levels of chemotactic factors protein expression at the fracture site in different time points were detected with immunohistochemistry technology. RESULTS AND CONCLUSION: The percentage of green fluorescent protein positive cells to al cells at the fracture site was (3.011±0.911)%, (9.031±0.145)%, (12.064±0.145)% at 1, 5, 14 days postoperatively; and osteoblasts differentiated from bone marrow mesenchymal stem cells accounted for 50% of al the osteoblasts. After fracture, the stromal cel derived factor-1, colony stimulating factor, hepatocyte growth factor, monocyte chemoattractant protein-1, and matrix metal oproteinases-9 were expressed to varying degrees in the microenvironment, while the expression of granulocyte colony-stimulating factor was negative. The expression of stromal cel derived factor-1 in the fracture microenvironment was the highest, mainly due to the migration of bone marrow mesenchymal stem cells. Experimental findings indicate that, autologous bone marrow mesenchymal stem cells participate in and play an important role in bone healing. The stromal cel derived factor-1 plays an important role in promoting bone marrow mesenchymal stem cells migration and promoting bone healing.