中文摘要：

目的探讨碱性成纤维细胞生长因子（b FGF）和转化生长因子-β1（TGF-β1）复合骨髓间充质干细胞（BMSCs）以温敏性壳聚糖（TCH）为载体对大鼠退变椎间盘的修复作用。方法针刺法建立SD大鼠椎间盘退变模型,4周后核磁共振下观察退变效果。体外培养BMSCs,并用含增强型绿色荧光蛋白的腺病毒转染使带有增强型绿色荧光蛋白基因,作荧光标记。将椎间盘退变的SD大鼠分成4组,实验组A组使用b FGF＋TGF-β1＋BMSCs＋TCH凝胶移植入退变的椎间盘中,B组和C组分别使用BMSCs＋TCH凝胶和b FGF＋TGF-β1＋TCH凝胶,对照组D组使用PBS缓冲液。继续培养4周后核磁共振观察各组椎间盘的修复情况。HE、Masson染色、组织病理学观察各组椎间盘结构。逆转录PCR,Western blot检测各组髓核蛋白聚糖、Ⅱ型胶原、Sox-9、Ⅰ型胶原的表达。结果移植注射的BMSCs能在椎间盘中生长,呈类髓核分化。核磁共振结果显示：A组髓核信号明显高于其他3组,B组高于C组,D组髓核信号最低,硬脊膜受压,脊髓呈串珠状改变,各组间Pfirrmann分级结果差异有统计学意义（P〈0.05）。HE、Masson染色显示：A组椎间盘结构完整,髓核细胞数量优于其他3组,髓核和纤维环界限清楚,B组髓核数量多于C组,B组纤维环未见断裂,而C组可见断裂的纤维环,D组髓核细胞被杂乱的纤维组织取代。逆转录PCR、Western blot显示：A组蛋白聚糖、Ⅱ型胶原、Sox-9的表达最高,B组优于C组,D组表达最低（P〈0.05）。而Ⅰ型胶原的表达在4组之间差异无统计学意义（P〉0.05）。结论移植的BMSCs在退变椎间盘中能够存活,呈类髓核分化。b FGF＋TGF-β1＋BMSCs＋TCH凝胶复合体对退变的椎间盘具有明显修复作用。BMSCs＋TCH凝胶治疗退变椎间盘的效果优于b FGF＋TGF-β1＋TCH凝胶但低于b FGF＋TGF-β1＋BMSCs＋TCH凝胶复合体。

英文摘要：

Objective To evaluate the effects of the combination of basic fibroblast growth factor（ b FGF）,transforming growth factor-β1（ TGF-β1）,bone marrow mesenchymal stem cells（ BMSCs）,and temperature-responsive chitosan hydrogel（ TCH） gel on the repair of degenerative intervertebral disc in rat models. Methods Rat models of intervertebral disc degeneration were established by acupuncture. The degenerative effects were observed under magnetic resonance imaging（ MRI）. The BMSCs was cultured in vitro and then transfected by adenovirus with enhanced green fluorescent protein to make it carry the gene of enhanced green fluorescent protein,which functioned as fluorescence labeling. The SD rat models of intervertebral disc degeneration were divided into four groups： group A,treated with the combination of b FGF,TGF-β1,BMSCs,and TCH gel; group B, treated with the combination of BMSCs and TCH gel; group C, treated with the combination of b FGF, TGF-β1, and TCH gel; and group D, treated with PBS buffer solution. After the corresponding reagents were injected into the degenerative intervertebral discs of each group, the rats were cultivated for another four weeks and then the repair effects of the intervertebral discs were observed under MRI.Furthermore,the intervertebral discs of each group were taken out and observed by HE and Masson staining. The nucleus pulposus was aspirated and the expressions of aggrecan,collagen Ⅱ,Sox-9,and collagen I of nucleus pulposus of each group were tested by reverse transcription polymerase chain reaction and Western blot. Results The transplanted BMSCs survived in the intervertebral disc and differentiated into nucleus pulposus-like cells.MRI showed that： the signal intensity of the nucleus pulposus of group A was much higher than that of the rest groups,the signal intensity of group B was higher than that of group C,and the signal intensity of group D was the lowest,in which the dura mater spinalis was in compression and the spinal cord changed in beaded shape.The di