两种重组腺相关病毒介导增强型绿色荧光蛋白转染大鼠成骨细胞效率的体外研究

目的 比较2种不同重组腺相关病毒(rAAV)介导的增强型绿色荧光蛋白(EGFP)对大鼠成骨细胞的转染效率,评价其作为成骨细胞病变基因治疗载体的可行性.方法 采用Ⅰ型胶原酶阶段消化法分离培养大鼠成骨细胞并鉴定,rAAV-EGFP按转染复数(MOI) 1×10~3、1×10~4、1×10~5、5×10~5分为只加rAAV和rAAV与腺病毒(ADV)共同转染组转染成骨细胞,倒置荧光显微镜观察转染后荧光强度随转染时间的变化,流式细胞仪检测rAAV2/6-EGFP和rAAV2/9-EGFP对成骨细胞的转染效率及荧光强度,确定转染的较佳MOI值,以此值用MTT法描绘细胞生长曲线,观察rAAV对细胞的毒性.结果 分离培养的细胞具有体内成骨细胞的生物学行为,rAAV对成骨细胞的转染效率随MOI值的增加而提高,ADV(-)组荧光强度在第5 d达到高峰,当MOI为1×10~5时,rAAV2/6-EGFP和rAAV2/9-EGFP的转染效率分别为90.2%、66.1%,MOI值增到5×10~5时转染效率无显著提高;ADV(+)组荧光强度在第3 d即达高峰,MOI值为5×10~5时,rAAV2/6-EGFP和rAAV2/9-EGFP的转染效率为47.6%、30.5%.细胞生长正常,rAAV对细胞活性影响小.结论 两种病毒载体对成骨细胞转染效率均较高,其中rAAV2/6高于rAAV2/9,是一种理想的基因治疗载体.

In vitro Study on Two Kind of Recombinant Adeno-associated Virus-mediated Transfection Efficiency with Enhanced Green Fluorescent Protein into Rats Osteoblasts

Objective To compare the transfection efficiency of two kind of recombinant adeno-associated virus-mediated transfection to rats osteoblasts with enhanced green fluorescent protein and assess the feasibility of it as a vector for gene therapy of osteoblast lesions. Methods The osteoblasts of rats were isolated, cultured and identified with typeⅠcollagen staged digestion method. According to different multiplicity of infection (MOI) (MOI=1×10~3,1×10~4,1×10~5,5×10~5), rAAV-EGFP was transfected into osteoblasts with rAAV only and rAAV-ADV co-transfection respectively. The expression of EGFP along with the transfection time was observed under inverted fluorescence microscope. The transfecion efficiency and fluorescence intensity was evaluated by flow cytometry. The best MOI value was analysed and the cell growth curves were obtained according to the best MOI value to evaluate the toxical effects of rAAV-EGFP. Results The cultured cells possessed the biological behaviors of osteoblasts. The transfecion efficiency of the rAAV was increased with the increasing of MOI. The EGFP expression reached the maximum on day 5 in ADV(-) group, the transfection efficiency of rAAV2/6-EGFP and rAAV2/9-EGFP was 90.2% and 66.1% respectively when MOI was 1×10~5 and no significant increasewas observedwhen MOI was 5×10~5. In ADV(+) group, EGFP expression reached its maximum on day 3, the transfection efficiency of rAAV2/6-EGFP and rAAV2/9-EGFP was 47.6% and 30.5% respectively when MOI was 5×10~5. And no significant biologic effects on the cyto-activity was observed. Conclusion The transfection efficiency of two kind of virus vectors was both very high and rAAV2/6's is higher than that of rAAV2/9. This suggested the potential of rAAV-EGFP as a safe and efficient vector for gene therapy.