大动物体内促组织工程骨成骨及血管化手段的研究

目的：探讨组织工程骨能否修复大动物大段负重骨骨缺损,筋膜瓣能否及如何促进组织工程骨体内成骨及血管化的过程。方法：中国青山羊9只作为空白组,制备单侧胫骨2cm的骨膜与肌缺损,缺损内不植入任何填充物,术后行放射性核素骨显像（ECT）、X线检查、组织学方法评价骨缺损自行修复情况。27只中国青山羊根据骨缺损植入物的不同分为3组：单纯材料组（单纯珊瑚羟基磷灰石coral hydroxyapatite,CHAP）、组织工程骨组（CHAP 经诱导分化的骨髓基质干细胞bone marrow stroma cell,BMSc）、筋膜瓣组（筋膜包裹CHAP 经诱导分化的BMSc）。组织工程骨组和筋膜瓣组分别取9只山羊的BMSc体外进行诱导分化,之后与CHAP复合。制备皮下带蒂深筋膜瓣。各组按不同的设计方案分别植入到骨缺损内。术后2、4、8周行ECT检查,4、8、12周行X线检查、组织学（V-G染色）检查,12周行生物力学检查。结果：术后各项检查结果表明,空白组山羊胫骨2cm的骨缺损是其自身无法修复的,因此是一个理想的骨缺损模型。单纯材料组未能修复骨缺损,仅表现出一个缓慢的爬行替代过程;组织工程骨组可基本修复骨缺损,在成骨质量和血管化过程方面表现出较理想的结果;筋膜瓣组修复骨缺损的效果更为满意,成骨质量和血管化程度亦高于组织工程骨组。结论：山羊胫骨2cm缺损模型不能自主成骨,符合骨组织工程实验的要求。组织工程骨具有良好的修复山羊大段骨缺损的能力。筋膜瓣促组织工程骨成骨的作用是通过其促进组织工程骨血管化这一方式实现的。

The method of accelerating osteanagenesis and revascularization of tissue engineered bone in big animal in vivo

To study whether tissue engineered bone can repair the large segment bone defect of large animal or not.To observe what character the fascia flap played during the osteanagenesis and revascularization process of tissue engineered bone.Methods 9Chinese goats were made2cm left tibia diaphyseal defect.The repairing effect of the defects was evaluated by ECT,X-ray and histology.27goats were divided into three groups:group of CHAP,the defect was filled with coral hydroxyapatite(CHAP);group of tissue engineered bone,the defect was filled with CHAP+bone marrow stroma cells(BMSc);group of fascia flap,the defect was filled with CHAP+BMSc+fascia flap.After finished culturing and inducing the BMSc,CHAP of group of tissue engineered bone and of fascia flap was combined with it.Making fascia flap,different materials as described above were then implanted separately into the defects.Radionuclide bone imaging was used to monitor the revascularization of the implants at2,4,8weeks after operation.X-ray examination,optical density index of X-ray film,V-G staining of tissue slice of the implants were used at4,8,12weeks after operation,and the biomechanical character of the specimens were tested at12weeks post operation. Results In the first study,the defect showed no bone regeneration phenomenon.2cm tibia defect was an ideal animal model.In the second study,group of CHAP manifested a little trace of bone regeneration,as to group of tissue engineered bone,the defect was almost repaired totally.In group of fascia flap,with the assistance of fascia flap which gave more chance to making implants to get more nutrient,the repair was quite complete.Conclusions The model of2cm caprine tibia diaphyseal defect cannot be repaired by goat itself and can satisfy the tissue engineering' s demands.Tissue engineered bone had good ability to repair large segment tibia defect of goat.Fascia flap can accelerate the revascularization process of tissue engineered bone.And by this way,it augment the ability of tissue engineered bone to repair the large bone defect of goat.