Kidneys grown in rats could pave way for human use

TOKYO, Feb 06 (AFP): Scientists said on Wednesday they have successfully used mice stem cells to grow kidneys in rat embryos, using a technique that could one day help grow human kidneys for transplant.

But the researchers cautioned that their success was only a first step and that "serious technical barriers and complex ethical issues" remain before the process could be used for human organs.

The technique has previously been used to grow mice-derived pancreases in rats, but the new study is the first evidence that it could one day provide a solution to the massive shortage of donor kidneys for people with renal disease.

The research, published on Wednesday in the Nature Communications journal, began with the development of a suitable "host" in which the kidneys could be grown.

The researchers collected rat embryo structures that had been genetically modified so they would not develop kidneys on their own.

The embryos were then injected with pluripotent stem cells from mice and implanted into rat wombs so they could be carried to term.