Tiny Livers, Tiny Steps
Whole organs building themselves out of what seems to be
thin air has been a fantasy of any number of made-for-TV science fiction movies.
Researchers in Japan, on the other hand, no longer have to rely on bad
entertainment after watching it physically become reality right before their
eyes. An article
from NPR recently covered the production of tiny livers formed from, well,
nothing -- using induced pluripotent stem cells (IPSC).
According to the article, laboratories around the world have
been trying to produce organs from stem cells for year, usually using a type of
three dimensional plastic scaffolding that the cells could stick to in order to
grow the necessary tissue. Takanori Takebe, MD, led the team of researchers
from Yokohama City University in developing a new technique for growing the
organs -- simply allow them to build themselves -- and it worked. By mixing
IPSC with other types of cells, the research team was able to grow “tiny 3D
structures that looked and acted like miniature livers, or ‘liver buds.’”
“There have been groups that have attempted to generate
liver cells, and that’s been promising,” said George Daley, MD, PhD, of the
Harvard Stem Cell Institute, in the NPR article. “This is the first attempt to
regenerate the organ by mixing the cells that are critical components of that
The “liver buds” had grown to 5 mL in five days and, because
they had been mixed with other cells, were capable of building blood vessels. Later,
the tiny livers were implanted into test mice and functioned “as a regular
liver would,” “[breaking] down human drugs and [making] blood proteins.” Prior
to the liver buds, scientists had used the plastic scaffolding to grow
synthetic organs like tracheas and had succeeded in implanting the laboratory
organs into a few patients, but “more complex organs -- kidneys, pancreases and
livers” had remained unsuccessful.
New technology is re-shaping the healthcare industry. Despite
being a breakthrough in IPSC research, safety remains a concern for the tiny “liverettes”
as stem cells have been known to form tumors. The potential for stem cell
research stands to advance in great leaps and bounds in the coming years. As
such, professionals have guarded optimism.rded optimism.