[Application of enhanced green fluorescent protein labeling technology to monitoring marrow mesenchymal stem cells migration after bone fracture].
摘要
OBJECTIVE: To monitor the stem cell migration into the bone defect following an injection of the labeled mesenchymal stem cells (MSCs) by the enhanced green fluorescent protein (EGFP) technology and to provide insights into an application of MSCs for the fracture healing. METHODS: Isolated MSCs from the rabbit femur marrow were culture-expanded and were labeled by the transfection with the recombinant retrovirus containing the EGFP gene. Then, some labeled MSCs were cultured under the osteogenic differentiation condition and the phenotype was examined. After the fracture of their bilateral ulna, 18 rabbits were divided into two groups. The labeled MSCs were injected into the aural vein at 1 x 10(7) cells/kg in the experimental group and the unmarked MSCs were injected in the control group 24 hours before surgery, and 1 and 24 hours after surgery, respectively. Necropsies were performed 2 days after surgery in the two groups. The sections from the left defects were observed under the fluorescence microscope and the others were analyzed by the bright-field microscopy after the HE staining. RESULTS: The EGFP did not affect the MSCs viability. After the labeled cells were incubated in the osteogenic medium alkaline phosphatase, the calcium nodules were observed. All the rabbits survived. The tissue of haematoma was observed in the bone defects and the fluorescent cells were found in the experimental group, but no fluorescent cells existed in the control group. CONCLUSION: The EGFP-labeled MSCs can undergo osteogenic differentiation in vitro and can migrate into bone defects after their being injected into the peripheral vein.