Scientists in Japan feel they are a step closer to growing fully functioning replacement kidneys after a recent breakthrough in animals. While researchers have been successful in growing functional kidneys from human stem cells, they have been unable to grow the kidneys to full size because there has been no pathway for excreting urine. This leads to hydronephrosis. To resolve this challenge, Takashi Yokoo and fellow researchers added a drainage pathway and compatible bladder to connect a kidney generated from stem cells to a rat or pig’s existing bladder. They called this technique “stepwise peristaltic ureter” (SWPU) system. The researchers are hoping this new technique will resolve the current two challenges of fully growing a kidney and providing a urine excretion pathway.
More extensive research is needed to study the long term effects these stem-cell-generated kidneys have on the body. And while this is an ‘interesting step forward’ according to Professor Chris Mason, an expert in stem cells and regenerative medicine at University College London, this breakthrough is not guaranteed to work in humans and testing it in humans is still several years away.