Experimental Study Of RhVEGF165 In Combination With RhBMP-2 In Intertransverse Fusion

ObjectiveTo investigate the efficacy of bone formation and intertransverse fusion with fibrin glue combined with vascular endothelial growth factor165 (rhVEGF165) and recombinant human bone morphogenetic protein — 2 ( rhBMP - 2 ) .Methods1. Experimental animals grouping : 30 Japanese big ear rabbits were distributed to three groups. One group was treated with rhVEGF165/rhBMP - 2/ FG . The other two groups were treated with rhBMP - 2/FG and FG separately as control groups.2. Tissue engineering materials construction: FG was gained by mixing fi-brinogen, thrombin and CaCl₂ according to a certain method. rhVEGF165 and rhBMP-2 or rhBMP-2 alone was mixed into FG for transplantation.3. Transplantation surgery -. Expose the left transverse processes of the fifth and the sixth lumbar vertebrae. Rub out the posterior cortex of the transverse processes using a driller. Transplant the rhVEGF165/rhBMP -2/ FG, rhBMP— 2/FG and FG on to the exposed spongy bone separately.4. Evaluation of spinal fusion: The animals were killed and the lumbar vertebrae were anatomized out completely six weeks after transplantation surgery. The specimens were evaluated by manual palpation, X - ray imaging, biome-chanics and histology. The related data were analyzed by statistics.ResultsAt 6 week after operation, seven transverse process fusion were occurred in rhVEGF165/rhBMP-2/ FG group, four in rhBMP -2/FG group and none in FG group. The results of gray scale and area of plain radiograph of new bone formation showed that the bone specific mass and area of group A was significantly more than group B ( P < 0. 05 ). The stability and rigidity of biomechanics of group A was significantly better than group B(P <0.05). Significant osteogene-sis happened in group A. HE dyeing shows there are mature bone tissues in bone mass between transverse processes of the fusion specimens in rhVEGF165/ rhBMP - 2/FG and rhBMP - 2/FG. Masson dyeing shows collagen tissues are a-bundant in the trabecula of the specimens in rhVEGF165/rhBMP -2/FG.ConclusionThis study shows that fibrin glue combined with rhBMP2 and rhVEGF165 can ossify, and the efficacy of intertransverse fusion in rabbits is significantly better than the simple use of rhBMP -2. Meanwhile, the present study also authenticated that the rhVEGF165 can promote the ossification induced by rhBMP -2.