The Study Of Transplantation With Exogenous NGF And CPC Composite On Repairing Defect Of Bone

Objective To manufacture a new type of stuff named composite CPC/NGF by admixing exogenous nerve growth factor (NGF) and calcium phosphate bone cement (CPC) to repair bone defect by transplantation. Observe whether the composite CPC/ NGF can promote bone formation. Try to offer a new method for bone formation.Methods To randomly divided 40 New Zealand male rabbits (weight from 1.5 to 3.0 Kg, mean weight 2.0 Kg) into group contrast (group C, n=20) and group experiments (group E, n=20). To establish 1.5cm bone defect on the right radial bone in all rabbits from two groups. Composite NGF/CPC was implanted in right radial bones in group E, CPC was implanted in right radial bones in group C. Then randomly selected 5 rabbits respectively from each group at four time points (2 weeks, 3 weeks, 4 weeks, and 8 weeks after transplantation). To observe osteoplastic situation in every time point by mean of X-ray, cell morphology observation, scanning electron microscope (SEM), BMP-2 immunohistochemistry stain.Results1 Gross anatomy observation showed newly formed bone in group E were more than that in group C at prophase, but the bone defect was agglutinated in 8 weeks.2 By direct comparison, bone formation score and bone density measurement through X-ray, we found the bone density in group E is more than that in group C at 2 weeks, 3 weeks and 4 weeks after transplantation (P<0.05), but no significant difference between two groups at 8 weeks after transplantation.3 By histomorphology observation under light microscope, we found the new bone in implanted area in group E is more than that in group C, and the mature situation of bone trabecular in group E is better than that in group C, but bone trabecular has ossified at 8 weeks, the is no difference between two groups.4 By mean of SEM, we found ripe bone trabecula has been formed in implanted area of composite CPC/NGF at 3 weeks, and there is an interfacing on superficies of graft. But there is less ripe bone trabecula in implanted area of NGF, and no interfacing was found on graft.5 By mean of BMP-2 immunohistochemistry stain, we found masc bone cell number in group E is significantly more than that in group C at 3 weeks and 4 weeks (P<0.05) .Conclusion The experiment has showed that the composite CPC/NGF can promote the growth of bone tissue. And as a new type of artificial bone which can repair bone defect.