July 7, 2022

Pigs could grow human organs in stem cell innovation

Scientists have discovered a way to make chimeric animals that have organs belonging to another species by injecting stem cells into an embryo of the other species.
Scientists
have discovered a way to make chimeric animals that have organs belonging to
another species by injecting stem cells into an embryo of the
other species. The researchers injected rat stem cells into the embryos of mice
that had been genetically modified so that they could not produce their own
organs, creating mice with rat organs. The researchers say the technique could
be used to grow human organs in pigs using patients’ own stem cells, for use as
transplants. By using a patient’s own stem cells, it could help to lower the
risk of the patient’s body rejecting the transplanted organ, while also
providing a rich supply of donor organs.

Current
organ shortages mean that patients must face long waiting lists for
transplants. Professor Hiromitsu Nakauchi, of the University of Tokyo in Japan
and who led the research, said:

“Our ultimate goal is to generate human organs from
induced pluripotent stem cells. The technique, called blastocyst
complementation, provides us with a novel approach for organ supply. We have
successfully tried it between mice and rats. We are now rather confident in
generating functional human organs using this approach.”

Professor Nakauchi and his team used a type of adult
stem cell known as induced pluripotent stem cells, which can be taken from a
tissue sample such as skin and encouraged to grow into any type of cell found
in the body. With his colleagues, he injected these cells extracted from rats
into the embryos of mice that were unable to develop their own pancreas, the
organ that produces vital hormones such as insulin. When the mice grew to
adulthood, they showed no signs of diabetes and had developed a pancreas that had
been formed almost entirely from the injected rat stem cells.

The researchers claim that the rat stem cells grew in
the space left by the missing mouse pancreas and so almost any organ could be
grown in this manner. If developed for use with human stem cells, the technique
could foster a way of treating diabetic patients by providing a way of
replacing their pancreas. Professor Nakauchi said they hoped to further trial
the technique by growing other organs and were also seeking approval to use
human stem cells. They have, however, already produced pigs that were able to
produce human blood by injecting human blood cells into pig foetuses.

He said:

“For ethical reasons we cannot make an organ
deficient human embryo and use it for blastocyst complementation. So to make
use of this system to generate human organs, we must use this technique using
blastocysts of livestock animals such as pigs instead. Blastocyst
complementation across species had never been tested before, but we have now
shown that it can work.” ~ Independent,
Jun 19

 

Pigs could grow human organs in stem cell innovation
Jared Yee
stem cells