Page 28 - ARUBA TODAY

A28 SCIENCE
Friday 27 January 2017

Scientists take first steps to growing human organs in pigs

MALCOLM RITTER Scientists used human stem of any proposed work.
AP Science Writer cells, which are capable of A pig might not always
NEW YORK (AP) — Scientists producing a wide variety have to be brought to
have grown human cells of specialized cells. They in- term, Belmonte and Wu
inside pig embryos, a very jected pig embryos made said. Even a pig fetus might
early step toward the goal in the lab with three to 10 of provide human pancreatic
of growing livers and other those cells apiece, and im- cells to treat diabetes, or
human organs in animals to planted the embryos into kidney cells to repair injuries
transplant into people. sows. At three to four weeks to that organ, they said.
The cells made up just a tiny of development, 186 em- The University of Minneso-
part of each embryo, and bryos were removed and ta’s Garry said the research
the embryos were grown examined. offers some direction about
for only a few weeks, re- Less than 1 in every 100,000 what kind of human stem
searchers reported Thurs- embryonic cells was hu- cells will work best. And it
day. man, which still comes to shows a need for boosting
Such human-animal re- about a million human the number of human cells
search has raised ethical This undated photo provided by the Salk Institute on Jan. 24, cells, Wu said. That con- that appear in the embryo,
2017 shows a 4-week-old pig embryo which had been injected
concerns. The U.S. govern- with human stem cells. tribution is lower than ex- he said.
ment suspended taxpayer Associated Press pected, he said, “but we Hiromitsu Nakauchi of Stan-
funding of experiments in were very happy to see we ford University said his own
2015. The new work, done achieved, he said, put- age of human donors for actually can see the hu- unpublished experiments
in California and Spain, was ting human cells in animals transplants. man cells after four weeks with pig and sheep em-
paid for by private founda- could pay off for studies of The Salk team is working on of development.” bryos also found a sparse
tions. how genetic diseases de- making humanized pan- The cells generated the contribution from injected
Any growing of human or- velop and for screening creases, hearts and livers precursors of muscle, heart, human cells. That’s a chal-
gans in pigs is “far away,” potential drugs. in pigs. The animals would pancreas, liver and spinal lenge for making organs,
said Juan Carlos Izpisua Animals with cells from dif- grow those organs in place cord tissue in the embryos. but it might be surmounted
Belmonte of the Salk Insti- ferent species are called of their own, and they’d be The researchers said they by focusing cells on doing
tute in La Jolla, California, chimeras (ky-MEER’-ehz). euthanized before the or- plan to test ways to focus that job, he said.
an author of the paper in Such mixing has been gan is removed. human cells on making Ethics experts were also im-
the journal Cell. done before with mice and Most of the organ cells specific tissues while avoid- pressed by the results. “It re-
He said the new research rats. Larger animals like pigs would be human. By inject- ing any contribution to the ally does give a green light
is “just a very early step to- would be needed to make ing pig embryos with stem brain, sperm or eggs. to explore more,” said In-
ward the goal.” human-sized organs. That cells from the person who That addresses ethical con- soo Hyun of Case Western
Even before that is could help ease the short- will get the transplant, the cerns that the approach Reserve University in Cleve-
problem of rejection should could accidentally lead land.
be minimized, said another to pigs that gain some hu- Hyun said he understood
Salk researcher, Jun Wu. man qualities in their brains, why some people might
Daniel Garry of the Univer- or make human egg or object on moral grounds
sity of Minnesota, who is sperm. to making animals with hu-
working on chimeras but There was no sign of that in man organs.
didn’t participate in the the new research. The gov- “It seems kind of creepy,”
new work, called the Cell ernment, meanwhile, has he said. But “this is a strat-
paper “an exciting initial signaled that it may lift the egy to help save human
step for this entire field.” federal funding ban soon lives” and so it is justified if
Here’s what the new paper
reports: but impose extra oversight properly done, he said.q