Raw264.7细胞向破骨细胞分化诱导培养体系的改良

Improved induction culture system for Raw264.7 cells to differentiate into osteoclasts

目的:通过改良细胞培养方案建立体外诱导Raw264.7细胞分化形成成熟破骨细胞(OC)的高效培养体系。方法:向Raw264.7细胞培养液α-MEM中添加50μg·L-1 M-CSF、100μg·L-1 RANKL和1×10-8 mol·L-1 1α,25-(OH)2D3,于5%CO2、37℃孵箱中培养12d,每3d换液1次,每次换液前对细胞进行短暂消化。倒置显微镜下观察细胞形态变化,并利用HE染色、抗酒石酸酸性磷酸酶(TRAP)染色、FITCphalloidin染色和免疫荧光染色鉴定OC是否成熟并具有吞噬功能。结果:通过改良培养方法,在诱导过程中培养孔内的大部分区域始终保持单层细胞的生长状态。镜下观察和HE染色,诱导第12天时OC胞体覆盖培养面积的70%;FITC-phalloidin染色,伴随着OC成熟,伪足内出现的束状伪足小体逐渐变为环形,最终融合带状肌动蛋白环环绕在胞质周围;免疫荧光染色,诱导12d后OC表达的降钙素受体(CTR)较前体细胞显著增加,TRAP染色显示OC胞浆内呈现大量红色颗粒。提示获得的OC成熟并具有吞噬功能。结论:本实验通过改良培养方法,联合应用细胞因子50μg·L-1 M-CSF、100μg·L-1 RANKL和1×10-8 mol·L-1 1α,25-(OH)2D3建立了体外诱导Raw264.7细胞分化形成成熟OC的高效培养体系。

Objective To establish a high-performance induction culture system for Raw264.7 cells to differentiate into osteoclasts（OC）invitro by improving the cell culture program.Methods The Raw264.7 cells were cultured withα-MEM medium containing 50 μg × L-1 M-CSF, 100 μg × L-1 RANKL, and 1 · 10-8 mol × L-1 1α,25-（OH）2 D3 in 5% CO2 for 12 d at 37℃. The cells were digested transiently every time before the medium was changed after every three days. The morphologic changes of the Raw264.7 cells were observed by inverted microscope.The maturation and phagotrophic function of OC were identified by HE,TRAP,FITC-phalloidin staining and immunofluorescence.Results The cells remained to grow in single layers all the time in most areas of the well during the whole induction by the improved culture program. The observation results of inverted microscope and HE staining showed that the growth area of the polykaryotic OC reached to 70% of the well on day 1 2. FITC-phalloidin staining showed that in the maturation of the OC, the cluster-shaped podosomes in the pseudopodia gradually transformed into rings,which finally fused to form a large belt surrounding the periphery of the cytoplasm. The calcitionin receptor （CTR） expressed by OC was markedly enhanced compared with the precursor cells by immunofluroescence staining,and a large number of red granules appeared in the cytoplasm of OC with TRAP staining on day 1 2. These results comfirmed that the obtained OC were maturated and owned phagotrophic function. Conclusion A high-performance induction culture system for Raw264. 7 cells to differentiate into OC in vitro induced by combination of 50μg × L-1 M-CSF, 100μg × L-1 RANKL,and 1 · 10-8 mol×L-1 1α,25-（OH）2 D3 is established by improving the cell culture program.