Featured Research

from universities, journals, and other organizations

Skin cells transformed into functioning liver cells in mouse study

Date:
February 23, 2014
Source:
Gladstone Institutes
Summary:
An important breakthrough has been made that could affect patients waiting for liver transplants. Scientists have discovered a way to transform skin cells into mature, fully functioning liver cells that flourish on their own, even after being transplanted into laboratory animals modified to mimic liver failure. In previous studies on liver-cell reprogramming, scientists had difficulty getting stem cell-derived liver cells to survive once being transplanted into existing liver tissue. But this team figured out a way to solve this problem, and have revealed a new cellular reprogramming method that transforms human skin cells into liver cells that are virtually indistinguishable from the cells that make up native liver tissue.

Liver (stock illustration). A new cellular reprogramming method has been revealed that transforms human skin cells into liver cells that are virtually indistinguishable from the cells that make up native liver tissue.
Credit: Sebastian Kaulitzki / Fotolia

The power of regenerative medicine now allows scientists to transform skin cells into cells that closely resemble heart cells, pancreas cells and even neurons. However, a method to generate cells that are fully mature -- a crucial prerequisite for life-saving therapies -- has proven far more difficult. But now, scientists at the Gladstone Institutes and the University of California, San Francisco (UCSF), have made an important breakthrough: they have discovered a way to transform skin cells into mature, fully functioning liver cells that flourish on their own, even after being transplanted into laboratory animals modified to mimic liver failure.

In previous studies on liver-cell reprogramming, scientists had difficulty getting stem cell-derived liver cells to survive once being transplanted into existing liver tissue. But the Gladstone-UCSF team figured out a way to solve this problem. Writing in the latest issue of the journal Nature, researchers in the laboratories of Gladstone Senior Investigator Sheng Ding, PhD, and UCSF Associate Professor Holger Willenbring, MD, PhD, reveal a new cellular reprogramming method that transforms human skin cells into liver cells that are virtually indistinguishable from the cells that make up native liver tissue.

These results offer new hope for the millions of people suffering from, or at risk of developing, liver failure -- an increasingly common condition that results in progressive and irreversible loss of liver function. At present, the only option is a costly liver transplant. So, scientists have long looked to stem cell technology as a potential alternative. But thus far they have come up largely empty-handed.

"Earlier studies tried to reprogram skin cells back into a pluripotent, stem cell-like state in order to then grow liver cells," explained Dr. Ding, one of the paper's senior authors, who is also a professor of pharmaceutical chemistry at UCSF, with which Gladstone is affiliated. "However, generating these so-called induced pluripotent stem cells, or iPS cells, and then transforming them into liver cells wasn't always resulting in complete transformation. So we thought that, rather than taking these skin cells all the way back to a pluripotent, stem cell-like state, perhaps we could take them to an intermediate phase."

This research, which was performed jointly at the Roddenberry Center for Stem Cell Research at Gladstone and the Broad Center of Regeneration Medicine and Stem Cell Research at UCSF, involved using a 'cocktail' of reprogramming genes and chemical compounds to transform human skin cells into cells that resembled the endoderm. Endoderm cells are cells that eventually mature into many of the body's major organs -- including the liver.

"Instead of taking the skin cells back to the beginning, we took them only part way, creating endoderm-like cells," added Gladstone and CIRM Postdoctoral Scholar Saiyong Zhu, PhD, one of the paper's lead authors. "This step allowed us to generate a large reservoir of cells that could more readily be coaxed into becoming liver cells."

Next, the researchers discovered a set of genes and compounds that can transform these cells into functioning liver cells. And after just a few weeks, the team began to notice a transformation.

"The cells began to take on the shape of liver cells, and even started to perform regular liver-cell functions," said UCSF Postdoctoral Scholar Milad Rezvani, MD, the paper's other lead author. "They weren't fully mature cells yet -- but they were on their way."

Now that the team was encouraged by these initial results in a dish, they wanted to see what would happen in an actual liver. So, they transplanted these early-stage liver cells into the livers of mice. Over a period of nine months, the team monitored cell function and growth by measuring levels of liver-specific proteins and genes.

Two months post-transplantation, the team noticed a boost in human liver protein levels in the mice, an indication that the transplanted cells were becoming mature, functional liver cells. Nine months later, cell growth had shown no signs of slowing down. These results indicate that the researchers have found the factors required to successfully regenerate liver tissue.

"Many questions remain, but the fact that these cells can fully mature and grow for months post-transplantation is extremely promising," added Dr. Willenbring, associate director of the UCSF Liver Center and the paper's other senior author. "In the future, our technique could serve as an alternative for liver-failure patients who don't require full-organ replacement, or who don't have access to a transplant due to limited donor organ availability."


Story Source:

The above story is based on materials provided by Gladstone Institutes. Note: Materials may be edited for content and length.


Journal Reference:

  1. Saiyong Zhu, Milad Rezvani, Jack Harbell, Aras N. Mattis, Alan R. Wolfe, Leslie Z. Benet, Holger Willenbring, Sheng Ding. Mouse liver repopulation with hepatocytes generated from human fibroblasts. Nature, 2014; DOI: 10.1038/nature13020

Cite This Page:

Gladstone Institutes. "Skin cells transformed into functioning liver cells in mouse study." ScienceDaily. ScienceDaily, 23 February 2014. <www.sciencedaily.com/releases/2014/02/140223131703.htm>.
Gladstone Institutes. (2014, February 23). Skin cells transformed into functioning liver cells in mouse study. ScienceDaily. Retrieved July 30, 2014 from www.sciencedaily.com/releases/2014/02/140223131703.htm
Gladstone Institutes. "Skin cells transformed into functioning liver cells in mouse study." ScienceDaily. www.sciencedaily.com/releases/2014/02/140223131703.htm (accessed July 30, 2014).

Share This




More Health & Medicine News

Wednesday, July 30, 2014

Featured Research

from universities, journals, and other organizations


Featured Videos

from AP, Reuters, AFP, and other news services

Generics Eat Into Pfizer's Sales

Generics Eat Into Pfizer's Sales

Reuters - Business Video Online (July 29, 2014) Pfizer, the world's largest drug maker, cut full-year revenue forecasts because generics could cut into sales of its anti-arthritis drug, Celebrex. Fred Katayama reports. Video provided by Reuters
Powered by NewsLook.com
Nigeria Ups Ebola Stakes on 1st Death

Nigeria Ups Ebola Stakes on 1st Death

Reuters - Business Video Online (July 29, 2014) Nigerian authorities have shut and quarantined a Lagos hospital where a Liberian man died of the Ebola virus, the first recorded case of the highly-infectious disease in Africa's most populous economy. David Pollard reports Video provided by Reuters
Powered by NewsLook.com
Running 5 Minutes A Day Might Add Years To Your Life

Running 5 Minutes A Day Might Add Years To Your Life

Newsy (July 29, 2014) According to a new study, just five minutes of running or jogging a day could add years to your life. Video provided by Newsy
Powered by NewsLook.com
Ebola Outbreak Poses Little Threat To U.S.: CDC

Ebola Outbreak Poses Little Threat To U.S.: CDC

Newsy (July 29, 2014) The Ebola outbreak in West Africa poses little threat to Americans, according to officials with the Centers for Disease Control and Prevention. Video provided by Newsy
Powered by NewsLook.com

Search ScienceDaily

Number of stories in archives: 140,361

Find with keyword(s):
Enter a keyword or phrase to search ScienceDaily for related topics and research stories.

Save/Print:
Share:

Breaking News:
from the past week

In Other News

... from NewsDaily.com

Science News

Health News

Environment News

Technology News



Save/Print:
Share:

Free Subscriptions


Get the latest science news with ScienceDaily's free email newsletters, updated daily and weekly. Or view hourly updated newsfeeds in your RSS reader:

Get Social & Mobile


Keep up to date with the latest news from ScienceDaily via social networks and mobile apps:

Have Feedback?


Tell us what you think of ScienceDaily -- we welcome both positive and negative comments. Have any problems using the site? Questions?
Mobile: iPhone Android Web
Follow: Facebook Twitter Google+
Subscribe: RSS Feeds Email Newsletters
Latest Headlines Health & Medicine Mind & Brain Space & Time Matter & Energy Computers & Math Plants & Animals Earth & Climate Fossils & Ruins