Mature liver cells can turn into stem cells!

Liver is known to regenerate itself, but can liver cells be reverted to a stem-cell like state? Yes, researchers say.

The finding can pave the way for liver cells transplant to cure genetic liver disorders.

Researchers at the Harvard Stem Cell Institute, led by Fernando Camargo, stumbled upon this fact while investigating whether a biochemical cascade called "Hippo", which controls how big the liver grows, also affects the cell's fate.

"I think this study highlights the tremendous plasticity of mature liver cells," said Camargo, an associate professor at Harvard University's department of stem cell and regenerative biology.

The researchers found that switching off the Hippo-signalling pathway in mature liver cells generates very high rates of dedifferentiation.

This means the cells turn back the clock to become stem-cell like again, thus allowing them to give rise to functional progenitor cells that can regenerate a diseased liver.

Even if three-quarters of a liver is surgically removed, duplication alone could return the organ to its normal functioning mass.

This new research indicates that there is a second mode of regeneration that may be repairing constant liver damage.

"It is not that you have a very small population of cells that can be recruited to an injury. Almost 80 percent of liver cells can undergo this cell fate change," Camargo added.

"The next step," Camargo said, "would be to figure out how Hippo's activity changes in cells affected by chronic liver injury or diseases such as hepatitis."

In the long term, this work could lead to drugs that manipulate the Hippo activity of mature liver cells in patients to spur dedifferentiation and hasten healing.

It might also be possible to control Hippo signalling to grow countless liver progenitor cells in a laboratory dish for transplant.

The findings were published in the journal Cell.