Department of Stem Cells and Developmental Biology, Cell Science Research Center, Royan Institute for Stem Cell Biology and Technology, ACECR, PO Box 19395-4644, Tehran, Iran.
Stem Cell Rev Rep. 2013 Aug;9(4):493-504. doi: 10.1007/s12015-011-9330-y.
The generation of human induced pluripotent stem cells (hiPSCs) with a high differentiation potential provided a new source for hepatocyte generation not only for drug discovery and in vitro disease models, but also for cell replacement therapy. However, the reported hiPSC-derived hepatocyte-like cells (HLCs) were not well characterized and their transplantation, as the most promising clue of cell function was not reported. Here, we performed a growth factor-mediated differentiation of functional HLCs from hiPSCs and evaluated their potential for recovery of a carbon tetrachloride (CCl4)-injured mouse liver following transplantation. The hiPSC-derived hepatic lineage cells expressed hepatocyte-specific markers, showed glycogen and lipid storage activity, secretion of albumin (ALB), alpha-fetoprotein (AFP), urea, and CYP450 metabolic activity in addition to low-density lipoprotein (LDL) and indocyanin green (ICG) uptake. Similar results were observed with human embryonic stem cell (hESC)-derived HLCs. The transplantation of hiPSC-HLCs into a CCl4-injured liver showed incorporation of the hiPSC-HLCs into the mouse liver which resulted in a significant enhancement in total serum ALB after 1 week. A reduction of total serum LDH and bilirubin was seen when compared with the control and sham groups 1 and 5 weeks post-transplantation. Additionally, we detected human serum ALB and ALB-positive transplanted cells in both the host serum and livers, respectively, which showed functional integration of transplanted cells within the mouse livers. Therefore, our results have opened up a proof of concept that functional HLCs can be generated from hiPSCs, thus improving the general condition of a CCl4-injured mouse liver after their transplantation. These results may bring new insights in the clinical applications of hiPSCs once safety issues are overcome.
具有高分化潜能的人诱导多能干细胞（hiPSC）的产生不仅为药物发现和体外疾病模型提供了新的肝细胞来源，也为细胞替代疗法提供了新的来源。然而，据报道，hiPSC 衍生的肝样细胞（HLC）的特征描述并不完善，其移植作为细胞功能最有前途的线索尚未报道。在这里，我们通过生长因子介导的分化，从 hiPSC 中获得功能性 HLC，并评估了它们在移植后恢复四氯化碳（CCl4）损伤的小鼠肝脏中的潜在应用。hiPSC 衍生的肝谱系细胞表达了肝细胞特异性标志物，具有糖原和脂质储存活性，能够分泌白蛋白（ALB）、甲胎蛋白（AFP）、尿素和 CYP450 代谢活性，此外还能够摄取低密度脂蛋白（LDL）和吲哚菁绿（ICG）。人胚胎干细胞（hESC）衍生的 HLC 也观察到了类似的结果。将 hiPSC-HLC 移植到 CCl4 损伤的肝脏中，观察到 hiPSC-HLC 整合到小鼠肝脏中，导致移植后 1 周血清总 ALB 显著增加。与对照组和假手术组相比，移植后 1 周和 5 周时，血清总 LDH 和胆红素均有所降低。此外，我们在宿主血清和肝脏中分别检测到了人血清 ALB 和 ALB 阳性的移植细胞，这表明移植细胞在小鼠肝脏中实现了功能整合。因此，我们的研究结果为从 hiPSC 中生成功能性 HLC 提供了概念验证，从而改善了 CCl4 损伤的小鼠肝脏在移植后的整体状况。一旦解决了安全性问题，这些结果可能会为 hiPSC 的临床应用带来新的见解。
