How he did it
Takebe and his team grew the organ using induced pluripotent stem cells (iPS), created by reprogramming human skin cells to an embryo-like state. The researchers placed the cells on growth plates in a specially designed medium; after nine days, analysis showed that they contained a biochemical marker of maturing liver cells, called hepatocytes.
At that key point, Takebe added two more types of cell known to help to recreate organ-like function in animals: endothelial cells, which line blood vessels, taken from an umbilical cord; and mesenchymal cells, which can differentiate into bone, cartilage or fat, taken from bone marrow. Two days later, the cells assembled into a 5-millimeter-long, three-dimensional tissue that the researchers labelled a liver bud an early stage of liver development.
Thanks, I didn’t see pluripotent cells mentioned in the original article. That in itself is telling.