Jan 14, 2008 -- Using the shells of dead hearts as scaffolds, scientists have created beating, "bio-artificial" rat and pig hearts.
There's still a long way to go -- but University of Minnesota researcher Doris Taylor, PhD, and colleagues say the results hold promise as a new source of human hearts and other organs for transplant.
"We just took nature's own building blocks to build a new organ. When we saw the first heartbeats, we were speechless," Taylor colleague Harald C. Ott, MD, now at Massachusetts General Hospital, said in a video news release.
The researchers first took the heart from a dead rat and washed it in detergents to get rid of all the dead cells. All that was left behind was the fibrous shell of the dead heart.
They then injected the heart with a mixture of living, immature heart cells taken from young rats. Next, they attached the heart to a "bioreactor" that provided nourishment and electrical stimulation. Eight days later, the heart began to beat.
Taylor and colleagues did the same thing with a pig heart, "showing that this technology can be scaled to hearts of human size and complexity. We have also applied this technique to a variety of mammalian organs including lung, liver, kidney, and muscle," they report.
"At first we focused on the heart -- but our hope is, if you need it, we can make it," Taylor said in the video.
"If our research becomes applicable to humans, which we hope it will, it has the potential to save millions of lives," Ott said.
There are major hurdles to overcome. One is to find a source of cells to repopulate the dead-heart scaffold. Taylor and colleagues hope to be able to use stem cells for this purpose, as taking living cells from a donor heart would require too many hearts to be practical.
Another hurdle is to show that these laboratory-grown hearts can function inside a living animal.
Taylor and colleagues report their findings in the Jan. 13 online issue of the journal Nature.