With all the parts, grown, the kidney was placed inside a rat, then the pathway was added, followed by the bladder they'd grown—the new bladder was then connected to the rat's native bladder. After sewing up the rat, they found the whole system worked. The team then repeated what they had done with a much larger animal, one much closer in size to humans—a pig—and found the same results. The paper was published in the journal Proceedings of the National Academy of Sciences.
This research brings us one step closer to growing a fully functioning replacement kidneys for human patients who suffer from kidney failure. Statistics show that over 1 million patients die annually from untreated kidney failure. Creating customized kidneys from stem cells could solve the problem of shortage of donors and save millions of lives.