Vascular Endothelial Growth Factor Gene Transfection Bone Marrow Stromal Cells Establish Scaffold To Treat The Ischemic Necrosis Of Lunate Bone Of Dogs

Objective:To observe the capability of vascular endothelial growth factor gene transfect bone marrow stromal cells ployglycolic-acid (AdVEGF165-BMSCs-PGA) grafts in the repairs of the ischemic necrosis of lunate bone of dogs made in liquid nitrogen to provide a new basic method on clinical treatment of Kienbock's disease.Methods: Extraction the iliac bone marrow stromal cells of adult healthy dogs, in vitro purified and digested and passage by Trypsin, Scaffold establishment: a. seeded to absorbable polyglycolic-acid scaffold product BMSCs-PGA graft. b. then use liposome carrying fluorescent protein VEGF165 gene in shuttle plasmid transfer in cultured bone marrow stromal stem cells, seeded to absorbable polyglycolic-acid scaffold product AdVEGF165-BMSCs-PGA graft. Animal models: after intravenous anesthesia, the lunates were exposed dorsally, peeled off parenchyma and frozen by liquid nitrogen (LN). MRI confirmed the early necrosis of lunates of 12 dogs at three weeks postoperatively. Optimized models and transplantation: anesthetized and exposed lunates dorsally again, a cortical window of 5×10mm was made, through which as much cancerous bone was removed as possible, after the curettage, the cavity was filled with LN for 10 min, and the frozen bone was thawed at room temperature for 10 min, the freeze-thaw procedure was repeated three times. At last PGA grafts, BMSCs-PGA grafts, AdVEGF165-BMSCs-PGA grafts were transplanted into its target lunates cavities. Grouping: Frozen in LN on the establishment of bone ischemia and necrosis of 12 dogs were randomly divided into 3 groups, namely AdVEGF165-BMSCs-PGA transplantation group, BMSCs-PGA transplantation group and lunate bone necrosis PGA control group , with 4 dogs in each group. Measures: the vascularization grafts implanted into the defect necrosis area were evaluated by X-ray CT and MRI at 4,8,12 weeks postoperatively. The related gross observation, histological and immunohistochemical analysis were also involved. Observation of ischemic necrosis of the lunate revascularization and bone repair capacity.Results: 12 dogs were involved in the result analysis. Results of X-ray and histology demonstrated capability of repairing of ischemic necrosis of lunate bone at each time point of AdVEGF165-BMSCs-PGA transplantation group was higher than BMSCs-PGA transplantation group, PGA control group, the difference was significant(P<0.01). Immunohistochemistry results also showed that AdVEGF165-BMSCs-PGA transplantation group showed revascularization and bone repair capacity was more evident than on the latter two.Conclusion: VEGF165 in bone marrow stromal cells could promote early revascularization of ischemic necrosis of the lunate and improve the repair of bone defect, avoiding the secondary collapse.