Scientists in Massachusetts report using cells from cloned cow embryos to grow kidney-like organs that function and are not rejected when implanted into adult cows.

The research, described in an interview with The Washington Post by Robert P. Lanza, chief scientist on the project at Advanced Cell Technology in Worcester, MA, would mark the first use of cloning technology to grow genetically matched organs for transplantation.

If the approach can ultimately be used to make human kidneys from cloned human embryos, it could help address the human organ shortage that has more than 50,000 Americans currently waiting for a cadaver kidney to become available for a kidney transplant.

While it is not known whether the organs created cow embryons can perform all of the functions of a cow kidney, Lanza said "we can say clearly that these kidneys produced urine and survived for several months inside the cows."

Lanza said he was reluctant to reveal details of the work because the team hopes to publish the new results in peer-reviewed journals, which tend not to publish results that have been publicly released.

But he said the team took a single skin cell from an adult cow's ear and fused it with a cow's egg whose own genetic material had been removed, creating a cow embryo that they grew to an early fetal stage at which they identified immature cells starting to turn into kidney cells.

Other sources: Washington Post, Advanced Cell Technology