The experts managed to accelerate the development of the livers before transplanting them into rats.
Study senior author Dr. Alejandro Soto-Gutierrez is an associate professor of Pathology and faculty member of both the McGowan Institute for Regenerative Medicine and the Pittsburgh Liver Research Center.
“Seeing that little human organ there inside the animal – brown, looking like a liver – that was pretty cool. This thing that looks like a liver and functions like a liver came from somebody’s skin cells,” said Dr. Soto-Gutierrez.
The mini livers, which can be custom-made using a patient’s cells, secrete bile acids and perform other functions just like a normal liver.
While it takes up to two years for a liver to fully develop under natural conditions, the livers engineered by the Pittsburgh team matured in under a month.
The skin cells collected for the study were reprogrammed into stem cells that were manipulated to become various types of liver cells. The experts then removed all of the cells from a rat liver and replaced them with the human liver cells.
To put their work to the test, the researchers transplanted lab-grown mini livers into five rats who were bred to resist organ rejection. The team evaluated the animals four days after the transplant to check on the status of the livers.
The study revealed that the rats had human liver proteins in their blood serum, which meant the lab-made organs were working.
Dr. Soto-Gutierrez believes the research is not just a step toward growing replacement organs in a lab, but is also a useful tool in itself.
“The long-term goal is to create organs that can replace organ donation, but in the near future, I see this as a bridge to transplant,” said Dr. Soto-Gutierrez. “For instance, in acute liver failure, you might just need hepatic boost for a while instead of a whole new liver.”
The study is published in the journal Cell Reports.