再血管化的同种异体微小颗粒骨磷酸钙复合物修复骨缺损

Composite of revascularized micro-morselized allograft bone and calcium phosphate cement for repairing bone defect

目的:制备仿生化的组织工程人工骨,观察分析同种异体微小颗粒骨复合磷酸钙骨水泥修复兔桡骨节段性骨缺损的效果。方法:实验于2004-03/2005-01在哈尔滨医科大学组织工程实验室完成。①选取44只3月龄健康日本大耳白兔作为受体,随机分为3组:组织工程人工骨组36只(兔左侧桡骨缺损),磷酸钙颗粒骨复合物组36只(兔右侧桡骨缺损),空白对照组8只。②组织工程人工骨组、磷酸钙颗粒骨复合物组于双侧桡骨中段作纵形切口,显露桡骨,建立双侧桡骨15mm长的桡骨-骨膜缺损模型。③组织工程人工骨组植入自体微小颗粒骨、磷酸钙骨水泥、重组骨形态发生蛋白复合物,植入前该复合物与兔毛细血管内皮细胞、成骨细胞混合培养5d;磷酸钙颗粒骨复合物组单纯植入自体微小颗粒骨、磷酸钙骨水泥的复合物,不使用促骨化、血管化的细胞因子及种子细胞;空白对照组骨缺损区旷置,不予任何充填物。④各组术后每天肌注青霉素40万u,组织工程人工骨组、磷酸钙颗粒骨复合物组分别于术后4,8,12周取材,12只/次。进行影像学、组织学及电镜检查,观察人工骨的骨化、血管化以及骨缺损修复情况。结果:实验选取44只大耳白兔作为受体,全部进入结果分析。①放射学以及组织学检查结果显示,组织工程人工骨组、磷酸钙颗粒骨复合物组的骨缺损都获得了不同程度的修复,但组织工程人工骨组在成骨速度、成骨质量、血管化程度等方面均优于磷酸钙颗粒骨复合物组。②新生骨及新生血管定量分析表明,术后4,8,12周组织工程人工骨组的新生血管面积百分比、新骨形成面积百分比均优于磷酸钙颗粒骨复合物组(P<0.05)。结论:同种异体微小颗粒骨复合磷酸钙骨水泥制备的组织工程化人工骨能够加快人工骨骨化和血管化的进程,有效修复骨缺损。

AIM： To prepare the imitated tissue engineering artificial bone, and observe and analyze the effect of composite of revascularized micromorselized allograft bone and calcium phosphate cement in repairing segmental bone defect of rabbit radius. METHODS： This experiment was conducted at the Laboratory of Tissue Engineering, Harbin Medical University from March 2004 to January 2005. ① Altogether 44 3 month-old healthy Japanese flap-eared White rabbits were chosen as the receptors and randomly divided into 3 groups ： Tissue engineering artificial bone group （Group A, n=36）（left radius defect）, mixture of micro-morselized bone and calcium phosphate cement group （Group B, n=36） （right radius defect）, blank group （Group C, n=8）. ②Lognitudi- nal incision was created on the bilateral radius middle segment of the rabbits of Group A and Group B to expose radius. Then, bilateral radius periosteum defect models with 15 mm in length were developed.③ Micromorselized allograft bone and calcium phosphate cement, recombinant bone morphagenetic protein composite were transplanted into the rabbits of Group A . Before transplantation, the composite was co-cultured for 5 days with endothelial cells and osteoblasts of blood capillary; Composite of micro-morselized bone and calcium phosphate cement without cytokines or seed cells which promoting ossification and vascularization were transplant- ed into the rabbits of Group B; There was nothing transplanted onto the bone defect region in Group C. ④40×l0^4 U penicillin was intramuscularly injected into rabbits after operation in each group. Sample-collection was conducted in Group A and Group B at postoperative 4, 8 and 12 weeks, 12 rabbits once. Imaging, histological and electron microscope examination were performed to observe ossification, vascularization and bone defect re- pair of artificial bone. RESULTS： Totally 44 flap-eared white rabbits were enrolled as receptors, and all of them entered the stage of result analysis. ① Radiological and histological examination showed that all the bone defect in Group A and Group B were repaired to some extent. But ossified velocity, ossified mass, vascularized degrees and other aspects in the Group A were superior to those in Group B. ②Quantitative analysis on newly formed bone and new vessels demonstrated that percent of new vessels area and percent of. newly formed bone in Group A were superior to those in Group B at postoperative 4, 8 and 12 weeks （P〈0.05）. CONCLUSION： Tissue-engineerod artificial bone prepared with micromorselized allograft bone and calcium phosphate cement can speed up the progression of ossification and vascularization of artificial bone and repairbone defect effectively.