This study demonstrates the efficient generation of human hepatocyte-like cells from induced pluripotent stem (iPS) cells. The research shows that mouse iPS cells can fully develop into fetal livers in vivo, and a protocol was established to generate highly differentiated human hepatocyte-like cells from iPS cells that display key liver functions and can integrate into the hepatic parenchyma in vivo. The protocol uses well-defined culture conditions to support efficient and reproducible differentiation of iPS cells into the hepatocyte lineage. The generated hepatocyte-like cells express key liver markers and display several known hepatic functions, including glycogen synthesis, lipid accumulation, and drug metabolism. Additionally, the cells were shown to integrate into the mouse liver parenchyma in vivo, indicating their potential for therapeutic applications. The study highlights the potential of iPS cells as a source of patient-specific hepatocytes for research and therapeutic purposes, particularly in the context of liver disease. The findings suggest that iPS-derived hepatocytes could be used for drug screening, toxicological studies, and the study of liver diseases. However, the study also notes that the expression of certain enzymes, such as those involved in drug metabolism, is not fully recapitulated in iPS-derived hepatocytes compared to adult liver samples. The study concludes that the developed protocol can efficiently and reproducibly generate hepatocyte-like cells from human iPS cells under well-defined culture conditions.This study demonstrates the efficient generation of human hepatocyte-like cells from induced pluripotent stem (iPS) cells. The research shows that mouse iPS cells can fully develop into fetal livers in vivo, and a protocol was established to generate highly differentiated human hepatocyte-like cells from iPS cells that display key liver functions and can integrate into the hepatic parenchyma in vivo. The protocol uses well-defined culture conditions to support efficient and reproducible differentiation of iPS cells into the hepatocyte lineage. The generated hepatocyte-like cells express key liver markers and display several known hepatic functions, including glycogen synthesis, lipid accumulation, and drug metabolism. Additionally, the cells were shown to integrate into the mouse liver parenchyma in vivo, indicating their potential for therapeutic applications. The study highlights the potential of iPS cells as a source of patient-specific hepatocytes for research and therapeutic purposes, particularly in the context of liver disease. The findings suggest that iPS-derived hepatocytes could be used for drug screening, toxicological studies, and the study of liver diseases. However, the study also notes that the expression of certain enzymes, such as those involved in drug metabolism, is not fully recapitulated in iPS-derived hepatocytes compared to adult liver samples. The study concludes that the developed protocol can efficiently and reproducibly generate hepatocyte-like cells from human iPS cells under well-defined culture conditions.