Can science make human organs

Artificial organs: Human mini liver works in rats

Researchers at the University of Pittsburgh School of Medicine used human skin cells to create a fully functional mini-liver that they then transplanted into rats. In this proof-of-concept experiment, the laboratory-made organs survived in their animal hosts for four days. The mini-organ was able to excrete bile acid and urea just like a normal liver.

The scientists created the miniature liver by first reprogramming human skin cells into stem cells. This is now a well-established biotechnological method. The stem cells made them transform into different types of liver cells. The researchers then transplanted these into a rat liver in the laboratory, gradually removing all of the animal cells. What takes up to two years in a natural environment only takes less than a month in the bioreactor.

As a final test, the Pittsburgh team transplanted the lab-grown mini liver into five rats. Four days after the procedure, it examined the condition of the implanted organs. In all cases, blood circulation problems had developed inside and around the graft, but the liver was functioning.

"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 transplantation," said Alejandro Soto-Gutierrez, lead author of the study and professor of pathology at the University of Pittsburgh . "In acute liver failure, for example, you may only need a liver surge instead of a whole new liver for a while." However, Soto-Gutierrez said there are still considerable challenges to be overcome, including long-term survival and safety issues.