Beating Heart Created in Lab
Heart From Dead Rat Beats After Repopulation With Live Cells
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.
"Going forward, our goal is to use a patient's stem cells to build a new
heart," Taylor said in a news release.
"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
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.