A team of Japanese scientists from the Yokohama City University have developed a fully functional human liver from stem cells derived from skin and blood.
Deemed to be medical breakthrough, the creation could pave way for developing much-needed livers and other transplant organs in a laboratory. While it could take a decade to actually grow organs for transplants in a laboratory, the discovery comes across as a ‘proof of concept’ for embarking more ambitious organ-growing experiments, researchers say.
Appreciating the success of the research, Dusko Illic, a stem cell expert at King’s College London who was not directly involved in the study said, “The promise of an off-the-shelf liver seems much closer than one could hope even a year ago.”
He further added that while the technique looks “very promising” and represents a huge step forward, “there is much unknown and it will take years before it could be applied in regenerative medicine.”
The study
Previous findings have established the presence of two categories of stem cells — embryonic stem cells, ones that are harvested from embryos, and reprogrammed “induced pluripotent stem cells” (iPS cells), usually taken from skin or blood.
For the purpose of the current study, researchers used iPS cells to create three different cell types – hepatic endoderm cells, mesenchymal stem cells and endothelial cells. These cell types usually combine in the natural formation of a human liver in a developing embryo. The cell types were then mixed together to see if they grow.
Interestingly, the cells grew and formed three-dimensional structures called “liver buds”. Liver buds are a collection of liver cells that have the potential to grow into a full organ.
The developed cells were then transplanted into mice wherein they matured and connected themselves to the host’s blood vessels. These matured liver buds then began to perform many of the functions of mature human liver cells.
“To our knowledge, this is the first report demonstrating the generation of a functional human organ from pluripotent stem cells,” researchers marked. The findings offered “distinct possibility of being able to create mini livers from the skin cells of a patient dying of liver failure and transplant them to boost the failing organ.”
The findings of the study are reported in the journal Nature.
