绿色荧光蛋白标记人脂肪基质细胞成骨分化能力体外实验研究

目的研究绿色荧光蛋白(GFP)基因体外转染人脂肪基质细胞的方法,并检测基因转染后细胞的生物学特性及分化潜能。方法体外分离培养人脂肪基质细胞,用重组腺病毒载体Ad-GFP及脂质体介导质粒pEGFP-C1两种方法转染GFP基因,通过流式细胞术观察比较GFP转染和表达的结果;倒置显微镜下观察细胞生长情况;将腺病毒介导的基因转染细胞经成骨定向诱导后,检测碱性磷酸酶表达和钙结节形成情况。结果重组GFP基因的腺病毒Ad-GFP转染的脂肪基质细胞的感染率达(42.5±1.5)%,16h即有GFP表达,7d时表达趋于稳定,感染6周时仍可见有GFP表达,明显优于脂质体转染组(转染效率最高为11.4%)。感染Ad-GFP后的脂肪基质细胞与未感染的对照组脂肪基质细胞成骨诱导分化后碱性磷酸酶(ALP)表达均逐渐增高,两组间差异无统计学意义(P>0.05);诱导21d后两组均见到茜素红钙盐染色阳性。结论重组GFP基因的腺病毒载体Ad-GFP可高效率感染脂肪基质细胞,基因转染后细胞的增殖分化能力未受到影响,可以作为一种高效可靠的人脂肪基质细胞标记方法。

A Study on Transfection of Green Fluorescence Protein Gene into Human Adipose Stromal Cells in vitro

OBJECTIVE: To make a comparison on the efficiency of two methods for transfecting Green Fluorescence Protein gene into human adipose tissue-derived stromal cells, and to study the biological properties and multipotential differentiation of gene-transfected cells. METHODS: The human subcutaneous adipose tissue was obtained, digested with one volume of collagenase type I, and then cultured with BGJb medium. After subculture and expansion, the human adipose tissue-derived stromal cells infected with Ad-GFP or liposome were observed and analyzed with fluorescence microscopy and flow cytometry to assess transfection efficiency. The growth curve of transfected adipose tissue-derived stromal cells was protracted. The adipose tissue-derived storomal cells were induced to differentiate into osteoblasts, and non-transfected cells were set as control. RESULTS: 42.5% +/- 1.5 of the human adipose tissue-derived stomal cells infected with Ad-GFP were found to express GFP at a level higher than that of the control of liposome (11.40%). Infected adipose tissue-derived stromal cells were noted to form mineralized nodes by the use of Alizarin Red stain. CONCLUSION: The human adipose tissue-derived stromal cells infected with Ad-GFP can express higher level of GFP, and can maintain the ability of proliferation and differentiation as the non-infected human adipose tissue-derived stromal cells do. The infected adipose tissue-derived stromal cells with Ad-GFP can track the change of adipose tissue-derived stromal cells in the study of multipotential differentiation and can serve as cellular vehicles for systemic gene delivery.