Department of Chemical Engineering and Materials Science, University of Minnesota, Minneapolis, MN 55455-0132, USA.
Tissue Eng Part A. 2011 Sep;17(17-18):2331-41. doi: 10.1089/ten.TEA.2010.0667. Epub 2011 Jun 30.
Hepatocyte-like cells derived from stem cells hold great potential for clinical and pharmaceutical applications, including high-throughput drug toxicity screening. We report a three-dimensional aggregate culture system for the directed differentiation of adult rat bone marrow-derived stem cells, rat multipotent adult progenitor cells, to hepatocyte-like cells. Compared to adherent monolayer cultures, differentiation in the aggregate culture system resulted in significantly higher expression level of liver-specific transcripts, including an increased albumin mRNA level, and higher levels of albumin and urea secretion. This coincides with the presence of significantly more cells that express intracellular albumin at levels found in primary hepatocytes. The differentiated cell aggregates exhibited cytochrome P450-mediated ethoxyresorufin-O-dealkylation and pentoxyresorufin-O-dealkylation activity. Consistent with these increased mature functions, cells within the aggregates were shown to have many ultrastructural features of mature hepatocytes by transmission electron microscopy. With the scalability of the aggregate culture system and the enhanced differentiation capability, this system may facilitate translation of generating hepatocytes from stem cells to technology.
由干细胞分化而来的肝细胞样细胞在临床和药物应用方面具有巨大的潜力，包括高通量药物毒性筛选。我们报告了一种三维聚集培养系统，用于诱导成年大鼠骨髓来源的干细胞和大鼠多能成体祖细胞向肝细胞样细胞的定向分化。与贴壁单层培养相比，在聚集培养系统中的分化导致肝特异性转录物的表达水平显著升高，包括白蛋白 mRNA 水平的增加，以及白蛋白和尿素分泌水平的升高。这与存在更多表达细胞内白蛋白的细胞相一致，其水平与原代肝细胞相似。分化后的细胞聚集物表现出细胞色素 P450 介导的乙氧基荧光素-O-去烷基化和戊氧基荧光素-O-去烷基化活性。与这些成熟功能的增加一致，通过透射电子显微镜显示，聚集物中的细胞具有许多成熟肝细胞的超微结构特征。由于聚集培养系统的可扩展性和增强的分化能力，该系统可能有助于将干细胞分化为肝细胞的技术转化。
