新型组织工程化人工骨的体外初步构建

背景L-聚乳酸可以用于制备骨组织工程支架材料 ,但存在某些缺陷 ,能否复合聚磷酸钙纤维、Ⅰ型胶原来改善材料性能,从而找到新的组织工程化骨体外构建方法?目的应用组织工程学技术,体外初步构建有活性的新型组织工程化人工骨.设计 体外构建细胞-材料复合体,自身对照前瞻性研究.地点和对象本研究在解放军第三军医大学西南医院骨科和兰州铁道医学院复合材料研究所完成,对象为 5例重庆市健康志愿者的髂骨骨髓.干预培养、诱导人骨髓间充质干细胞向成骨细胞表型分化,制备性能优越的新型支架材料,再按一定的方法体外构建细胞-材料复合体.主要观察指标细胞碱性磷酸酶染色的阳性率、扫描电镜观察组织工程化骨的微观结构.结果由 L-聚乳酸、聚磷酸钙纤维、Ⅰ型胶原制备出新型的骨组织工程复合支架材料,孔径 300～ 450 μ m,孔隙率 90.1%;细胞接种前碱性磷酸酶阳性率为(55± 8)%,接种后细胞可在材料内良好贴附生长,碱性磷酸酶阳性率为(52± 6)%,两者差异无显著性.结论经成骨诱导的间充质干细胞,可以与由 L-聚乳酸、聚磷酸钙纤维、Ⅰ型胶原制备的支架材料复合,在体外构建出组织工程化人工骨.

A preliminary study on the regeneration in vitro of the tissue-engineered bone

BACKGROUND:Poly-L-lactic acid(PLLA) has been successfully applied in bone tissue engineering. However,this scaffold is not optimal,and feasibility study is to be done with poly-L-lactic acid,calcium polyphosphate fiber(CPPf) and type Ⅰ collagen together. OBJECTIVE:To construct bioactive artificial bone in vitro with tissue-engineering technique. DESIGN:An auto-controlled trial is conducted for the prospective analysis of cell-material compound. SETTINGS and PARTICIPANTS:This experiment was performed in the Department of and Institute of Orthopaedics,Southwest Hospital,Third Military Medical University and Instiute of Composite Material,Lanzhou Railway College.Five cases of bone marrow taken from the iliac crest of normal donors ranging from 30 to 40 years old in Chongqing. INTERVENTIONS:Mesenchymal stem cells(MSCs) were isolated,expanded,differentiated into osteoblasts and the cell-scaffold complexes were constructed. MAIN OUTCOME MEASURE:The percent of positive cells stained for alkaline phosphatase with Gomori method and the density and porosity of the scaffolds. RESULTS:PLLA,CPPf and type Ⅰ collagen produced the novel scaffold composites(diameter of 300-450 μ m and porosity of 90.1% ).The percentage of positive cells was (55± 8)% before cells seeded,and it was (52± 6)% after the cell-scaffold complexes were incubated.Statistical differences of both groups were not significant. CONCLUSION:Induced MSCs can adhere to the novel scaffold composites and maintain the phenotype of osteoblast.This study provides new biosynthetic materials and methods for tissue-engineered bone regeneration in vitro.