转化生长因子-β1基因治疗对种植体周骨质疏松的影响

Effects of transforming growth factor-β1 gene therapy on bone rarefaction around endosseous implant

目的探讨转化生长因子-β1(TGF-β1)基因治疗对种植体周围骨质疏松和骨缺损的影响。方法构建pCDNA3.1(+)-TGF-β1真核表达载体,转染大鼠骨髓间充质干细胞(BMSCs),并与聚乳酸-羟基乙酸(PLGA)体外黏附。制备骨质疏松大鼠股骨植入钛种植体模型,将24只Wister大鼠随机分为实验组、对照组和空白对照组,实验组为在种植体周骨缺损处植入TGF-β1基因修饰BMSCs复合PLGA;对照组为BMSCs复合PLGA。术后第4和8周取标本行免疫组化和组织学分析,观察种植体周骨组织中TGF-β1的表达和组织学变化。结果术后第4周,实验组骨缺损区的TGF-β1表达较对照组和空白对照组明显;第8周实验组骨缺损区被新生骨充填,骨质较对照组和空白对照组明显改善。结论TGF-β1基因修饰BMSCs体内回植后,可在种植体周围骨组织内表达TGF-β1,并可以影响种植体周骨缺损的修复和骨质疏松状况。

Objective To investigate the effects of transforming growth factor-β1 （TGF-β1） gene therapy on bone defect and bone rarefaction around endosseous implant. Methods The primary cultured bone marrow derived stroma cells（BMSCs） was transfected by plasmid pCDNA3.1 （＋）-TGF-β1, and was adhered with polylactic-co-glycolic acid （PLGA） for constructing TGF-β1 gene-modified artificial bone. The model of rats with placed titanium implants in the proximal metaphyses of the tibiae after ovaxiectomy was made. The TGF-β1 gene-modified artificial hone（experimental group）, BMSCs-PLGA compound artificial bone （control group） and nothing （blank control group） were placed in the bone defect around implant. The tibiae were examined by decalcified sections with immunohistochemical method and histological analysis methods at intervals of 4 and 8 weeks after implant surgery in order to detect the expression of TGF-β1 in new bone adjacent to the implant and the healing of the bone defect around the implant. Results The expression level of TGF-β1 of experimental group was higher than that of control group and blank control group at the 4th week. The histological analysis indicated that the gene-modified artificial bone had stronger osetogenic potential than others. Conclusion TGF-β1 gene-modified artificial bone promotes the repair of the bone defect around titanium implants in osteoporotic rats.