The white whale of organ transplantation has always been to give patients an organ made from their own stem cells. In theory, it eliminates two major problems in one fell swoop: tissue shortages (i.e. insufficient organ donors) and immunocompatibility (eliminating the need for dangerous immunosupressive drugs). There have been many roadblocks to achieving this goal, including ethical and biological ones. However, a new study claims to have cleared some of the biological obstacles.
Researchers working together at several labs across Japan say they have created a lab-grown kidney that works in vivo.
Many groups have reported creating kidneys (and other organs, for that matter) in the lab, and many have reported getting the organs to survive inside an organism. However, this group, whose results appeared in the Proceedings of the National Academy of Sciences of the United States of America, is reportedly the first to be able to connect their lab-grown kidney to a mouse's excretory system and get the kidney to work (i.e. it produced urine on its own). Furthermore, the kidneys worked for the duration of the eight-week trial. After these successes in mice, the researchers moved on to pigs, where the kidney also worked well.
The trick appears to be that researchers did not just grow and implant a kidney, but drainage tubes and a bladder as well. Previous attempts that failed only implanted a lab-grown kidney and connected that directly to the organism's existing bladder.
As excited as many experts are about this discovery, they caution that we're still years away from translating these advances to humans.
Unfortunately, the U.S. has an immediate and dire need for kidneys. According to the Department of Health and Human Services, currently there are nearly 122,000 people on organ waiting lists, with 101,000 of those seeking a kidney. Last year 4,270 people died while waiting for a kidney transplant, while another 3,617 were removed from the list because they became too sick to still qualify.
Data from optn.transplant.hrsa.gov and OPTN/SRTR Annual Report. ** Data include deceased and living donors.
These numbers clearly outline a severe organ donation problem. Moreover, recent surveys say that 90 percent of Americans support the concept of organ donation, but just 30 percent say they know how to become a donor. So while we wait for science to catch up to the need, more needs to be done to close this sizable gap.