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目的运用基因重组的方法,对人转化生长因子β1(TRANSFORMING GROWTH FACTOR－β1)进行基因克隆,并在大肠杆菌中表达.同时观察其促进骨折愈合的作用.方法以 PBV 220作为原核细胞表达载体,将 TGF－ β1CDNA片段定向重组到 PBV 220的多克隆位点上,构建原核细胞表达性质粒PTGF－ β1,并转化至大肠杆菌中进行温度诱导表达.制造兔桡骨骨折模型,经皮注射重组 TGF－ β1,并与单纯挠骨骨折模型做对照.术后行X线和同位素骨显像检查.结果表达产物经SDS－PAGE分析,TGF－β1原核表达体系可高效表达 TGF－ β1,其表达产物占菌体可溶性蛋白的 23％.用大鼠肾成纤维细胞(NRK细胞)进行活性检测,该方法生产的 TGF－ β1具有该蛋白的野生生物学活性.术后 X线检查,实验组骨折愈合较对照组平均超前2周;同位素核素骨显像检查,实验组与对照组差异有显著性意义( P＜ 0 05).结论 TGF－β1原核表达体系的建立,为 TGF－ β1的生产提供了高效的表达工程菌,其表达产物能明显促进骨折愈合.“,”Objective By means of the method of gene recombinant, human transforming growth factor(TGF) β1 gene cloning was done by expressing the TGF -- β1 in escherichia coli, its activity of enhancing fracture healing was determined. Methods The plasmid TGF -- β1 was constructed by recovering TGF -- β1 cDNA fragment and inserted directly into PBV 220, a prokaryotic expression vector. The recombinant plasmid was transformed into E. colt to establish the prokaryotic expression system and induced to express encoded protein. The recombinant TGF -- β1 was injected into the established radius fracture in experimental group, and the radius fractures without TGF -- β1 injection was used as the control group. Results Radiographic examination after operation showed that bone union occurred in 3 weeks on most of the experimental group, and bone union occurred in 5 weeks on most of the control group. There is a statistical difference between experimental and control group(P < 0. 05) in skeletal scintigraphy. Conclusion The establishment of this system provides an efficient expression cell line for producing TGF --β1 and the recombinant TGF -- β1 can enhance fracture healing.