Application of Live Mitochondria Staining in Cell-Sorting to Purify Hepatocytes Derived from Human Induced Pluripotent Stem Cells

Human embryonic stem (ES) and induced pluripotent stem (iPS) cells have potential applications in cell-based regenerative medicine for treating severely diseased organs due to their unlimited proliferation and pluripotent properties. However, differentiating human ES/iPS cells into 100% pure target cell types is challenging due to their high sensitivity to the environment. Tumorigenesis after transplantation is caused by contaminated, proliferating, and undifferentiated cells, making high-purification technology essential for the safe realization of regenerative medicine. To mitigate the risk of tumorigenesis, a high-purification technology has been developed for human iPS cell-derived hepatocytes. The method employs FACS (fluorescence-activated cell sorting) using a combination of high mitochondrial content and the cell-surface marker ALCAM (activated leukocyte cell adhesion molecule) without genetic modification. 97% ± 0.38% (n = 5) of the purified hepatocytes using this method exhibited albumin protein expression. This article aims to provide detailed procedures for this method, as applied to the most current two-dimensional differentiation method for human iPS cells into hepatocytes.