Scientists have done the impossible and transplanted a lab-grown kidney into a living animal. Or to be specific, a living rat. It might sound crazy—and believe us, it is—but the success represents a major step toward the goal of growing personalized replacement organs and transplanting them into people with kidney failure. 

According to The Guardian who broke the story, there is no cure for kidney failure and "more than 51,000 people are treated every year in the UK for end-stage kidney failure." Worse still, 90% of them are on a waiting list for kidneys. Of course, there are transplants, but as The Guardian points out, those can seriously impede a person's quality of life as anyone on dialysis must limit their fluid intake, and the transplants only last between 10 and 15 years. 

Here's how the paper describes the experiment: 

Ott first took a rat kidney and stripped out its functional cells using a solution of detergent. That left behind a white cellular matrix, the collagen scaffold that gives the organ its three-dimensional structure.

His team then introduced kidney and blood vessel cells from newborn rats onto the scaffold and cultured the growing organ for 12 days, until the cells had grown to cover the scaffold. The team then implanted the organ into a living rat, where it successfully filtered the animal's blood and produced urine.

It probably won't be used on humans for some time, as the methods will need to be refined, said Massachusetts General hospital researcher Harald Ott, but here's hoping we're that much closer to a world with bioengineered kidneys. 

[via The Guardian]