Rohani L, Karbalaie K, Vahdati A, Hatami M, Nasr-Esfahani M H, Baharvand H
Department of Stem Cells, Cell Science Research Center, Royan Institute, Esfahan Campus, Esfahan, Iran
Int J Artif Organs. 2008 Mar;31(3):258-65. doi: 10.1177/039139880803100310.
Embryonic stem cells (ESCs) are of significant interest as a renewable source of nonproliferating cells. Differentiation of ESCs is initiated by the formation of embryoid bodies (EBs). Standard methods of EB formation are limited in their production capacity, in any variations in EB size and formation of EBs through frequent passages. Here we have reported the utility of a microencapsulation technique for overcoming these limitations by mass production of mouse ESCs in alginate beads called ESC spheres.
The mouse ESCs were encapsulated in 1.2% alginate solution and cocultured on a feeder layer. The cells were evaluated by flow cytometry, in vitro differentiation, immunofluorescence, and reverse transcriptase polymerase chain reaction (RT-PCR).
Analysis of encapsulated ESC spheres by flow cytometry showed similar percentages of Oct-4 and stage-specific embryonic antigen-1 (SSEA-1) expression in comparison with routine culture of ESCs. Moreover, the ESC spheres maintained a pluripotency potential which was comparable with ESCs cultured on feeder cells directly, as demonstrated by immunofluorescence and RT-PCR.
The results demonstrated that alginate encapsulation as a simple bioreactor, provides a scalable system for mass undifferentiated ESC sphere production with similar sizes and without the need for frequent passages for differentiation and clinical and pharmaceutical applications.
胚胎干细胞（ESCs）作为一种可再生的非增殖细胞来源备受关注。胚胎干细胞的分化是通过胚状体（EBs）的形成来启动的。标准的胚状体形成方法在生产能力、胚状体大小的任何变化以及通过频繁传代形成胚状体方面都存在局限性。在此，我们报道了一种微囊化技术的应用，该技术通过在称为ESC球的藻酸盐珠中大规模生产小鼠胚胎干细胞来克服这些局限性。
将小鼠胚胎干细胞封装在1.2%的藻酸盐溶液中，并在饲养层上进行共培养。通过流式细胞术、体外分化、免疫荧光和逆转录聚合酶链反应（RT-PCR）对细胞进行评估。
通过流式细胞术分析封装的ESC球，结果显示与胚胎干细胞的常规培养相比，Oct-4和阶段特异性胚胎抗原-1（SSEA-1）的表达百分比相似。此外，如免疫荧光和RT-PCR所示，ESC球保持了与直接在饲养细胞上培养的胚胎干细胞相当的多能性潜力。
结果表明，藻酸盐封装作为一种简单的生物反应器，为大规模生产大小相似的未分化ESC球提供了一个可扩展的系统，无需频繁传代即可用于分化以及临床和制药应用。
