Lab-Grown Kidneys Work In Vivo

Researchers show organoids grown from human stem cells can excrete urine when implanted in rats and pigs.

Sep 22, 2015
Tracy Vence

Seven to eight weeks after transplantation, urine from the transplant-grown bladder was continuously discharged from the connected host ureter.VIDEO COURTESY OF TAKASHI YOKOO A team led by investigators at the Jikei University School of Medicine in Tokyo has shown that mini kidneys grown in vitro from human stem cells can be connected to the excretory systems of rats and pigs. The results were published in PNAS yesterday (September 21).

Several groups have developed lab-grown mini kidneys, but connecting the organoids to a host animal’s excretory system has been a challenge. The Jikei University team applied an approach called stepwise peristaltic ureter (SWPU) to connect its lab-grown mini kidneys to the transplant recipient’s ureter. “To our knowledge, this is the first report showing that the SWPU system may resolve two important problems in the generation of kidneys from stem cells: construction of a urine excretion pathway and continued growth of the newly generated kidney,” the authors wrote in their paper.

“This is an interesting step forward. The science looks strong and they have good data in animals,” stem-cell researcher Chris Mason of University College London who was not involved in the work told BBC News. “It moves us closer to understanding how the plumbing might work.”