转染重组人骨形态发生蛋白-7基因对骨髓基质细胞生物学行为的影响

目的 观察重组人骨形态发生蛋白-7(rhBMP-7)基因转染骨髓基质细胞(BMSCs)后的稳定表达及表达产物对BMSCs生物学行为的影响。方法利用脂质体介导法将rhBMP．7基因转染BMSCs，以G418筛选出阳性克隆并扩大培养，用免疫组织化学链霉抗生物素蛋白-生物素-过氧化物酶复合物(SABC)法检测转基因细胞的稳定表达；转染48h后，用转基因细胞的培养液上清刺激正常培养的BMSCs，利用^3H标记的胞腺嘧啶氧核苷(^3H-TdR)掺入法、Na2^35SO4掺入法以及氯胺T法检测基因表达产物对BMSCs增殖、合成蛋白多糖以及胶原的影响。结果 转基因细胞4周时仍能表达外源性基因；基因表达产物能明显促进BMSCs的增殖以及蛋白多糖和胶原的合成。结论 rhBMP-7基因转染BMSCs后可获得稳定表达，且基因表达产物能促进BMSCs增殖。诱导其向软骨细胞分化并增强其生物学活性。

Effects of recombinant human BMP-7 gene transfection on bone marrow stromal cells in vitro

Objective To investigate the effects of recombinant human BMP-7 gene transfection on bone marrow stromal cells(BMSCs) in vitro.Methods BMSCs were transfected with rhBMP-7 gene through lipofectamine vector and selected by G418.Then the samples were tested by immunohistochemical staining.48 h after gene transfection,the supernatants were collected.After being exposed to the supernatants for another 48 h,BMSCs cultured in normal conditions were analyzed by 3H-TdR incorporation,Na 2 35SO 4 incorporation and chloramines-T.Results The expression of rhBMP-7 gene in transfected BMSCs was detectable in 4 weeks.The transgene expression products could stimulate the proliferation of BMSCs cultured in normal conditions and the biosynthesis of proteoglycan and collagen of BMSCs.Conclusion BMSCs have the potential for stable gene expression and the transgene expression products can induce BMSCs to differentiate to chondrocytes and enhance its bioactivity.Thus it is possible to use gene enhanced tissue engineering technology to repair articular cartilage defects.