Abstract: Methods of producing hepatocyte lineage cells are provided. The method can include transfecting a cell with one or more expression vectors. For example, a cell can be transfected with a first expression vector containing a first gene that encodes CCAAT/enhancer binding protein alpha (CEBPA), a second expression vector containing a second gene that encodes CCAAT/enhancer binding protein beta (CEBPB), a third expression vector containing a third gene that encodes forkhead box A1 (FOXA1), and a fourth expression vector containing a fourth gene that encodes forkhead box A3 (FOXA3). The method can include culturing the transfected cell obtained in a growth environment. The transfected cell can be cultured in Williams' E medium, ReproFF (feeder-free media maintaining pluripotency) medium, or both. Transfected and/or hepatocyte lineage cells obtained by a method of the present invention are also provided.

Abstract: Provided are a production method for hepatocyte lineage cells, a hepatocyte lineage cell or culture product obtained by the production method, and a hepatocyte differentiation-inducing medium. It has been found that the differentiation of iPS cells to hepatocyte lineage cells is efficiently induced by adding lactic acid or a salt thereof to a related-art hepatocyte differentiation-inducing medium.

Abstract: Provided are a method of inducing differentiation of pluripotent stem cells, such as induced pluripotent stem cells (hereinafter abbreviated as iPS cells), to hepatocytes in a short period of time, and a substance to be used in the method. Specifically, provided are a method of producing a cell culture formed substantially of hepatoblasts, the method including culturing pluripotent stem cells, such as iPS cells, in a culture medium having a composition shown in Table 1 below, and a culture medium for inducing differentiation of pluripotent stem cells into hepatoblasts, which has a composition shown in Table 1 below.

Abstract: Methods of producing hepatocyte lineage cells are provided. The method can include transfecting a cell with one or more expression vectors. For example, a cell can be transfected with a first expression vector containing a first gene that encodes CCAAT/enhancer binding protein alpha (CEBPA), a second expression vector containing a second gene that encodes CCAAT/enhancer binding protein beta (CEBPB), a third expression vector containing a third gene that encodes forkhead box A1 (FOXA1), and a fourth expression vector containing a fourth gene that encodes forkhead box A3 (FOXA3). The method can include culturing the transfected cell obtained in a growth environment. The transfected cell can be cultured in Williams' E medium, ReproFF (feeder-free media maintaining pluripotency) medium, or both. Transfected and/or hepatocyte lineage cells obtained by a method of the present invention are also provided.

Abstract: Provided are a method of inducing differentiation of pluripotent stem cells, such as induced pluripotent stem cells (hereinafter abbreviated as iPS cells), to hepatocytes in a short period of time, and a substance to be used in the method. Specifically, provided are a method of producing a cell culture formed substantially of hepatoblasts, the method including culturing pluripotent stem cells, such as iPS cells, in a culture medium having a composition shown in Table 1 below, and a culture medium for inducing differentiation of pluripotent stem cells into hepatoblasts, which has a composition shown in Table 1 below.

Abstract: The present invention relates to a differentiation inducing method comprising: introducing, into human induced pluripotent stem cells, a combination of genes of transcription factors which are possessed by fetal and adult hepatic cells, but are not possessed by human induced pluripotent stem cells; and adhering the human induced pluripotent stem cells to a substrate for monolayer culture in a medium containing a combination of growth-promoting agents for proliferation and differentiation, thereby enabling induction of the differentiation of the human induced pluripotent stem cells in large amounts in a short term, a hepatic progenitor cell produced by the method, and a cell composition for transplantation into the liver comprising the cell. The transcription factors include FOXA2, GATA4, HEX and C/EBP?, and the growth-promoting agents include oncostatin M, an epidermal growth factor, retinoic acid, dexamethasone, insulin, transferrin and a selenite ion.

Abstract: A means for feeder-free culture which can sufficiently maintain the undifferentiation potency of pluripotent stem cells such as iPS cells even without using heterologously derived cells or proteins, is provided.

Abstract: A metal ring loading and unloading apparatus is capable of loading and unloading a metal ring quickly and highly accurately for increased efficiency. The metal ring loading and unloading apparatus has a moving unit 41 slidably movable along a rail 48 which extends from a loaded ring placement unit 8 to an unloaded ring placement unit 11. On the moving unit 41, there are mounted a loaded ring delivering unit 9 for holding and delivering a metal ring W on the loaded ring placement unit 8 and an unloaded ring delivering unit 10 for removing the metal ring W from support rollers 3, 4 and delivering the metal ring W to the unloaded ring placement unit 11. The loaded ring placement unit 8 has a pressing unit for radially pressing the metal ring W to deform the metal ring W into a substantially elliptical shape. The loaded ring delivering unit 9 has a loaded ring gripping unit 26 for gripping the metal ring W deformed by the pressing unit.

Abstract: A metal ring loading and unloading apparatus is capable of loading and unloading a metal ring quickly and highly accurately for increased efficiency. The metal ring loading and unloading apparatus has a moving unit 41 slidably movable along a rail 48 which extends from a loaded ring placement unit 8 to an unloaded ring placement unit 11. On the moving unit 41, there are mounted a loaded ring delivering unit 9 for holding and delivering a metal ring W on the loaded ring placement unit 8 and an unloaded ring delivering unit 10 for removing the metal ring W from support rollers 3, 4 and delivering the metal ring W to the unloaded ring placement unit 11. The loaded ring placement unit 8 has a pressing unit for radially pressing the metal ring W to deform the metal ring W into a substantially elliptical shape. The loaded ring delivering unit 9 has a loaded ring gripping unit 26 for gripping the metal ring W deformed by the pressing unit.