兔角膜内皮细胞球形培养的活性和细胞表型

背景 组织工程角膜内皮层的构建和细胞注射疗法需要足够数量的角膜内皮细胞（CECs）,因此如何在体外培养大量高活性的角膜内皮种子细胞是当前亟需解决的问题. 目的 建立兔CECs高活性三维（3D）球形培养方法,探索培养细胞的生物学特性. 方法 酶消化法分离和培养兔CECs并进行传代,经低黏附振动培养法产生兔CECs球,倒置相差显微镜下观察培养细胞的形态;采用扫描电子显微镜观察CECs球的表面超微结构;用吖啶橙染色法鉴定CECs球中细胞的活性;采用CCK-8试剂盒检测细胞的吸光度（A450）值,判断细胞的增生情况.将CECs球接种到6孔细胞培养板贴壁培养1周,球形培养的细胞为球形培养组,常规培养的细胞为常规培养组.采用免疫荧光法检测闭锁小带蛋白1（ZO-1）和Na＋/K＋-ATP酶在细胞中的表达.结果 经球形培养的CECs呈聚集生长,培养1周细胞形态为六角形或多边形,融合成单层,呈铺路石状排列;扫描电子显微镜下可见兔CECs球体周围有细胞爬出,未长散的细胞球中细胞与细胞之间结合紧密,球体表面凹凸不平.吖啶橙染色表明,细胞球中90％细胞呈绿色荧光;球形培养组细胞平均A450值为1.524±0.013,常规培养组细胞平均A450值为1.265±0.021,球形培养组细胞增生值明显增加,2个组间差异有统计学意义（t=-3.436,P=0.010）.免疫荧光检测表明,培养的细胞中ZO-1和Na＋/K＋-ATP酶阳性细胞膜对FITC呈绿色荧光,细胞核DAPI染色呈蓝色荧光.结论 CECs的3D球形培养方法培养的细胞可保持细胞的高活性、高增生能力和细胞表型,为构建组织工程角膜内皮及细胞疗法提供了更好的角膜内皮种子细朐.

The viability and property of rabbit corneal endothelial cells by spheroid culture

Background The construction of tissue-engineered corneal endothelium and corneal endothelial cells （CECs） therapy need abundant seed cells,so how to culture a large amount of CECs with high viability and original cell properties is an urgent issue to be solved.Objective This study was to establish three-dimensional spheroid culture of CECs and explore the cellular biological characteristics.Methods Primary rabbit CECs were isolated with trypsin and subcultured.Low attachment and shaking culture was applied to form CECs spheres.Cultured cells were identified under the inverted microscope.The surface features of the cells were examined under the scanning electron microscope.The viability of the cells were assayed by acridine orange （AO） staining and CCK-8 kit.Then CECs spheres were incubated to 6-well plate for 1 week,and immunofluorescence staining was used to identify the expression of zonula occludens-1 （ZO-1） and Na＋/K＋-ATPase in the cells.The cell proliferation value of spheroid culture method was compared with that of regular culture method.Results CECs grew into aggregation after cultured with the hexagonal or polygonal shape and tight connection among the cells.The cells converged into single layer and slabstone-like arrangement 1 week later.Cells migrated out of the CECs sphere and formed an uneven spherical surface.The living cells showed green fluorescence for AO with the survival rate 90%.The absorbance （A450） of the cells was 1.524±0.013 and 1.265 ±0.021 in the spherical culture group and conventional culture group,respectively,showing a significant difference between them （t =-3.436,P=0.010）.The positive cells of ZO-1 and Na＋/K＋-ATPase showed the green fluorescence for FITC on cell membrane and blue fluorescence for DAPI on cell nucleus.Conclusions Spherical culture method maintains a high viability and proliferation ability of the cells and remains phenotype of CECs,which is superior to conventional culture method.This culture method provides better seeding CECs for the