Institute for Biomaterials and Biomedical Engineering, University of Toronto, Toronto, ON M5S 3E1, Canada.
Cell Stem Cell. 2012 Feb 3;10(2):218-29. doi: 10.1016/j.stem.2012.01.003.
Clinical hematopoietic transplantation outcomes are strongly correlated with the numbers of cells infused. Anticipated novel therapeutic implementations of hematopoietic stem cells (HSCs) and their derivatives further increase interest in strategies to expand HSCs ex vivo. A fundamental limitation in all HSC-driven culture systems is the rapid generation of differentiating cells and their secreted inhibitory feedback signals. Herein we describe an integrated computational and experimental strategy that enables a tunable reduction in the global levels and impact of paracrine signaling factors in an automated closed-system process by employing a controlled fed-batch media dilution approach. Application of this system to human cord blood cells yielded a rapid (12-day) 11-fold increase of HSCs with self-renewing, multilineage repopulating ability. These results highlight the marked improvements that control of feedback signaling can offer primary stem cell culture and demonstrate a clinically relevant rapid and relatively low culture volume strategy for ex vivo HSC expansion.
临床造血移植的结果与输注细胞的数量密切相关。预计造血干细胞（HSCs）及其衍生物的新治疗方法将进一步增加人们对体外扩增 HSCs 的策略的兴趣。在所有 HSC 驱动的培养系统中，一个基本的限制因素是分化细胞的快速产生及其分泌的抑制性反馈信号。本文描述了一种集成的计算和实验策略，通过采用受控的补料分批介质稀释方法，在自动化封闭系统过程中实现了对旁分泌信号因子的全局水平和影响的可调节降低。将该系统应用于人类脐血细胞，可在 12 天内快速增加具有自我更新、多谱系重编程能力的 HSCs11 倍。这些结果突出了反馈信号控制可为主要干细胞培养提供的显著改进，并证明了一种临床上相关的快速且相对低培养体积的体外 HSC 扩增策略。
