Qtracker体外标记兔成骨诱导分化后细胞的初步研究

目的 探讨Qtracker体外标记兔成骨诱导分化后细胞的特点及可行性.方法 抽取3个月龄健康新西兰大白兔骨髓,贴壁培养骨髓基质干细胞(BMSCs),传至第3代后向成骨细胞诱导,并做鉴定.Qtracker分别以1、2、4、8、16和32 nmol/10~6细胞的浓度标记成骨诱导分化后细胞,分别记为A、B、C、D、E、F组;未标记的细胞作为空白对照组(G组).分别利用荧光显微镜计数和流式细胞术两种方法枪测标记阳性率,台盼蓝拒染法检测标记后细胞存活率,甲基噻唑基四唑(MTT)法观察Qtracker染料对细胞增殖的影响.结果 兔BMSCs经诱导后能向成骨细胞诱导分化.经Qtracker标记后,荧光显微镜下胞浆呈绿色荧光.随着标记浓度的增加,A、B、C、D、E、F组细胞标记阳性率逐渐增高,于8 nmol/10~6细胞的浓度标记时,在荧光显微镜下计数,标记率可达到(93.58±2.08)%;通过流式细胞仪检测,其标记率为(95.24±1.31)%,经两种方法测定,D、E、F组间标记率差异均无统计学意义(P>0.05),且与其他各组比较差异均有统计学意义(P<0.05);G组各时间点标记阳性率均为0.以不同浓度标记后各组细胞存活率均在96%以上,且各组之间差异无统计学意义(P>0.05).标记Qtracker后对细胞的增殖无影响(P>0.05).结论 Qtracker可用于兔成骨诱导分化后细胞的体外标记,在浓度为8 nmol/10~6细胞下可得到最佳的标记率,且其对成骨诱导分化后细胞的增殖无明显影响.

Qtracker-labeled rabbit osteoblasts in vitro

Objective To explore the feasibility of labeling in vitro rabbit osteoblasts with Qtracker and the features of Qtracker-labeled rabbit osteoblasts. Methods A healthy male rabbit, 3 months old, weighing 2 kg, was used in this study. After bone marrow was aspirated, bone marrow stromal cells (BMSCs) were isolated and cultured using the adherence method in vitro. The third passage of BMSCs was induced into osteablasts before incubation with Qtracker at concentrations of 1, 2, 4, 8, 16, 32 nmol/10~6 cells (Groups A, B, C, D, E, F respectively). Cells not labeled by Qtracker served as negative control (Group G). The following parameters were measured: induction, differentiation and determination of rabbit osteoblasts; the optimal mass concentration of Qtracker labeling by fluorescence microscopy and flow cytometry; the cell sur-vival rates at various concentrations of Qtraeker labeling by trypan-blue exclusion; Qtracker-labeled cell pro-liferation by MTr. Results The primary and the passage rabbit BMSCs were chiefly of fusiform shape. Rabbit BMSCs differentiated into osteoblasts following induction. The osteoblasts cytoplasm showed green fluorescence under fluorescence microscopy after being labeled by Qtracker. The mean labeling rate increased with the increased concentration of Qtracker, reaching up to (93.58±2.08) % after incubation at 8 nmol/ 10~6 cells by fluorescence microscopy, and (95.24±1.31) % by flow cytometry. There were no significant differences between Groups D, E, F(P>0.05), but significant differences were found between Groups A, B, C and Groups D, E, F (P<0.05). The labeling rate for Group G was 0. The cell survival rates were all above 96% (P>0.05) . No significant differences were found in the cell proliferation among various con-centrations (P>0.05). Conclusions Qtraeker can be used as a labeling marker for rabbit osteoblasts. When the concentration is at 8 nmol/10~6 cells, optimal labeling effect can be achieved. Rabbit osteoblasts labeled with Qtracker are of high efficiency and safety.