可注射性藻酸钙凝胶修复整合兔膝关节骨软骨缺损实验研究

Experimental study on the repair and integration of acute osteochondral injury with injectable calcium alginate gel

目的: 使用骨髓基质干细胞 (BMSCs)、藻酸钙及两种生长因子, 修复兔股骨内髁负重区骨软骨缺损, 寻找合适的关节骨软骨缺损修复方法。方法: 将藻酸钙、体外培养扩增的自体BMSCs及IGF I+TGF β复合材料注射于兔膝关节股骨内髁负重区上的骨软骨缺损。结果: BMSCs在藻酸钙中能分化为软骨细胞和成骨细胞, 材料无毒副作用; 关节骨软骨缺损后注入BMSCs+藻酸钙 +IGF I+TGF β复合体, 各期修复较对照组均有统计学意义 (P<0. 05)。结论: 藻酸钙能为BMSCs提供良好三维生长环境并能使之保持正常形态; BMSCs+藻酸钙+IGF I+TGF β复合体能用于关节骨软骨急性缺损修复, 形成正常透明软骨样结构, 软骨下骨修复良好。

Objective:To evaluate the effect of bone marrow stem cells (BMSCs) in combination with injective calcium alginate gel,insulin-like growth factorⅠ(IGF-Ⅰ) and transforming growth factor β(TGF-β) on repairing the osteochondral defect in vitro.Method:Amplificated the BMSCs in vitro, then compounded it with the calcium alginate and the growth factors,then were injected into the defect of weight-bearing portions of medical femoral condyles in Zealand white rabbit,the specimens were taken and stained with HE stain, toluidine blue stain, Masson stain,and observed with transmission electron microscope etc.Result:Bone marrow stem cells differentiatied to chondroblasts or osteoblasts in the combination of calcium alginate gel,IGF-Ⅰ and TGF-β and finally regenerate cartilage and bone without immunological rejection and toxic reaction.The semiquantitative histological scores were significantly higher in the experimental group than that in the control group(P<0.01).Conclusion:Calcium alginate+stem cells+growth factors composite may succeed in the repair and integration of acute osteochondral injury. Alginate could keep the phenotype of marrow stem cells and serve as a carrier to fill osteochondral defects in vivo. The biodegradable matrix appears to provide a satisfactory 3-dimensional support in where is conducive to chondrogenesis.