St. Louis, June 24, 1998 -- Researchers at Washington University School of Medicine in St. Louis have found a novel way to grow new kidneys that may one day lessen the need for human donor organs. When they placed a developing rat kidney inside the abdominal cavity of an adult rat, it became a smaller version of an adult kidney.
"The organs look just like normal rat kidneys," says lead scientist Marc R. Hammerman, M.D., the Chromalloy Professor of Renal Diseases in Medicine and director of the Renal Division. Hammerman notes that their function needs to be improved before they can be of use, but he hopes the work could be used to develop transplantable kidneys that would be less likely to be rejected." More than 39,000 kidney patients currently are on the national waiting list of the United Network for Organ Sharing. In 1997, 2,000 people died waiting for a kidney.
Hammerman's results are published in the July issue of Kidney International. His wife, Nancy Hammerman, is a co-author. An art teacher in the Pattonville School District, Nancy Hammerman suggested that developing kidneys might be a source of transplants after hearing her husband give a transplant lecture in March 1996 in London, England.
Soon after, Hammerman and research instructor Sharon Rogers tried placing single developing kidneys under the capsule that covers the kidney of adult rats. The juvenile kidneys, as small as a pencil tip, are called metanephroi. They survived and grew "despite concern that the rats' immune defenses would attack the foreign organs." "They actually grew and developed into kidneys that you don't need to immunosuppress," Hammerman says.
The kidneys did not grow well, possibly due to tight quarters inside the
kidney capsule. But when the researchers placed the dots of kidney tissue inside
a sac-like membrane that surrounds and supports abdominal organs, they reached a
third of the size of an adult kidney within 6 wee
Contact: Barbra Rodriguez
Washington University School of Medicine