Department of Biochemistry and Molecular Biology, University of Calgary, AB, Canada.
J Tissue Eng Regen Med. 2012 Jun;6(6):462-72. doi: 10.1002/term.450. Epub 2011 Jul 14.
Induced pluripotent stem cells (iPSCs) can provide an important source of cells for the next-generation of cell therapies in regenerative medicine, in part due to their similarity to embryonic stem cells (ESCs). Patient-specific iPSCs represent an opportunity for autologous cell therapies that are not restricted by immunological, ethical and technical obstacles. One of the technical hurdles that must be overcome before iPSCs can be clinically implemented is the scalable, reproducible production of iPSCs and their differentiated progeny. All of the iPSC lines established thus far have been generated and expanded with static tissue culture protocols, which are time-consuming and suffer from batch-to-batch variability. Alternatively, stirred suspension bioreactors propose several benefits and their homogeneous culture environment facilitates the large-scale expansion required for clinical studies at less cost. We have previously developed protocols for expanding murine and human ESCs as undifferentiated aggregates in stirred suspension bioreactors. The resulting cells were karyotypically normal, expressed pluripotency markers and could be differentiated into all three germ lineages, both in vitro and in vivo. In this study, we demonstrate that stirred suspension bioreactors yield 58-fold expansion of undifferentiated pluripotent iPSCs over 4 days. In vitro differentiation into cartilage, bone and cardiomyocytes lineages, in addition to in vivo teratoma formation, further confirmed the existence of fully functional and undifferentiated pluripotent iPSC aggregates following long-term passaging. Stirred suspension bioreactor culture represents an efficient process for the large-scale expansion and maintenance of iPSCs, which is an important first step in their clinical application.
诱导多能干细胞（iPSCs）可以为再生医学中的下一代细胞疗法提供重要的细胞来源，部分原因是它们与胚胎干细胞（ESCs）相似。患者特异性 iPSCs 代表了自体细胞疗法的机会，不受免疫、伦理和技术障碍的限制。在 iPSCs 可以临床应用之前，必须克服的技术障碍之一是可扩展、可重复的 iPSCs 及其分化后代的生产。迄今为止建立的所有 iPSC 系都是通过静态组织培养方案生成和扩增的，这种方案既耗时又存在批次间变异性。相比之下，搅拌悬浮生物反应器具有多个优势，其同质的培养环境有利于以较低的成本进行临床研究所需的大规模扩增。我们之前已经开发了在搅拌悬浮生物反应器中作为未分化聚集体扩增鼠和人 ESC 的方案。所得细胞染色体核型正常，表达多能性标记物，并可在体外和体内分化为所有三个生殖系。在这项研究中，我们证明搅拌悬浮生物反应器在 4 天内可使未分化的多能 iPSCs 扩增 58 倍。体外分化为软骨、骨和心肌细胞谱系，以及体内形成畸胎瘤，进一步证实了经过长期传代后，存在完全功能和未分化的多能 iPSC 聚集体。搅拌悬浮生物反应器培养是 iPSCs 大规模扩增和维持的有效过程，是其临床应用的重要第一步。
