Japanese researchers have described in Nature
this week that they were able to make a functional human liver using induce pluripotent stem cells.
The liver was generated by transplanting liver buds (created in the laboratory) into mice, where the buds mature into tissue resembling the adult liver. Although it remains to be seen whether these techniques will work in human patients, the work provides a proof-of-concept that organ bud transplantation may represent a promising new approach towards regenerative medicine.
Commenting on the work, Stem Cells Australia's Program Leader Professor Martin Pera said, "Human pluripotent stem cells can be multiplied indefinitely in the laboratory, and they can turn into any type of cell in the body. These properties mean that stem cells could be used in transplantation therapy to replace damaged organs.
However, it has proven quite difficult to produce fully mature, functional human tissue from pluripotent stem cells grown in a petri dish. This exciting study shows that immature human liver cells, formed in laboratory cultures from pluripotent stem cells, can develop further and mature when they are grafted into a mouse.
The grafted human livers have the full functional capability of the adult organ, such as the capacity to metabolize drugs. The results demonstrate that the rich and complex environment of tissues in the adult body can help immature stem cell grafts to develop to an adult stage.
The report provides hope that even primitive tissues made from stem cells will one day restore function of dead or diseased organs in patients."
Japan's Yokohama City University grows new human liver made from stem cells inside mouse
[Herald Sun, 4 July 2013]