Featured Research

from universities, journals, and other organizations

New insights into how stem cells determine what tissue to become

Date:
August 2, 2010
Source:
University of Michigan
Summary:
Within 24 hours of culturing adult human stem cells on a new type of matrix, researchers were able to make predictions about how the cells would differentiate, or what type of tissue they would become.

This is an immunofluorescence image of a human mesenchymal stem cell growing on a plate of microposts, which have the approximate consistency of Silly Putty. This image was taken after one day of culturing. The red dots are the microposts, which are relatively short in this sample. The green is the cell and the blue is its nucleus. This cell will differentiate into a bone cell.
Credit: Michael T. Yang (University of Pennsylvania)

Within 24 hours of culturing adult human stem cells on a new type of matrix, University of Michigan researchers were able to make predictions about how the cells would differentiate, or what type of tissue they would become.

Their results are published in the Aug. 1 edition of Nature Methods.

Differentiation is the process of stem cells morphing into other types of cells. Understanding it is key to developing future stem cell-based regenerative therapies.

"We show, for the first time, that we can predict stem cell differentiation as early as Day 1," said Jianping Fu, an assistant professor in mechanical engineering and biomedical engineering who is the first author on the paper.

"Normally, it takes weeks or maybe longer to know how the stem cell will differentiate. Our work could speed up this lengthy process and could have important applications in drug screening and regenerative medicine. Our method could provide early indications of how the stem cells are differentiating and what the cell types they are becoming under a new drug treatment."

In this study, Fu and his colleagues examined stem cell mechanics, the slight forces the cells exert on the materials they are attached to. These traction forces were suspected to be involved in differentiation, but they have not been as widely studied as the chemical triggers. In this paper, the researchers show that the stiffness of the material on which stem cells are cultivated in a lab does, in fact, help to determine what type of cells they turn into.

"Our research confirms that mechanical factors are as important as the chemical factors regulating differentiation," Fu said. "The mechanical aspects have, until now, been largely ignored by stem cell biologists."

The researchers built a novel type of stem cell matrix, or scaffold, whose stiffness can be adjusted without altering its chemical composition, which cannot be done with conventional stem cell growth matrices, Fu said.

The new scaffold resembles an ultrafine carpet of "microposts," hair-like projections made of the elastic polymer polydimethylsiloxane -- a key component in Silly Putty, Fu said. By adjusting the height of the microposts, the researchers were able to adjust the rigidity of the matrix.

In this experiment, the engineers used human mesenchymal stem cells, which are found in bone marrow and other connective tissues such as fat. The stem cells differentiated into bone when grown on stiffer scaffolds, and into fat when grown on more flexible scaffolds.

Once the researchers observed the cells differentiating according to the mechanical stiffness of the substrate, they decided to measure the cellular traction forces throughout the culturing process to see if they could predict how the cells would differentiate.

Using a technique called fluorescent microscopy, the researchers measured the bending of the microposts in order to quantify the traction forces.

"Our study shows that if the stem cells determine to differentiate into one cell type then their traction forces can be much greater than the ones that do not differentiate, or that differentiate into another cell type," Fu said. "We prove that we can use the evolution of the traction force as early indicators for stem cell differentiation."

The new matrix -- manufactured through an inexpensive molding process -- is so cheap to make that the researchers are giving it away to any interested scientists or engineers.

"We think this toolset provides a newly accessible, practical methodology for the whole community," Fu said.

This work was conducted in Dr. Christopher Chen's group in the Department of Bioengineering at the University of Pennsylvania. The research was supported by the National Institutes of Health and the American Heart Association.


Story Source:

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


Journal Reference:

  1. Jianping Fu, Yang-Kao Wang, Michael T Yang, Ravi A Desai, Xiang Yu, Zhijun Liu & Christopher S Chen. Mechanical regulation of cell function using geometrically modulated elastomeric substrate. Nature Methods, 2010; DOI: 10.1038/nmeth.1487

Cite This Page:

University of Michigan. "New insights into how stem cells determine what tissue to become." ScienceDaily. ScienceDaily, 2 August 2010. <www.sciencedaily.com/releases/2010/08/100801190257.htm>.
University of Michigan. (2010, August 2). New insights into how stem cells determine what tissue to become. ScienceDaily. Retrieved July 25, 2014 from www.sciencedaily.com/releases/2010/08/100801190257.htm
University of Michigan. "New insights into how stem cells determine what tissue to become." ScienceDaily. www.sciencedaily.com/releases/2010/08/100801190257.htm (accessed July 25, 2014).

Share This




More Health & Medicine News

Friday, July 25, 2014

Featured Research

from universities, journals, and other organizations


Featured Videos

from AP, Reuters, AFP, and other news services

Beatings and Addiction: Pakistan Drug 'clinic' Tortures Patients

Beatings and Addiction: Pakistan Drug 'clinic' Tortures Patients

AFP (July 24, 2014) A so-called drugs rehab 'clinic' is closed down in Pakistan after police find scores of ‘patients’ chained up alleging serial abuse. Duration 03:05 Video provided by AFP
Powered by NewsLook.com
Too Few Teens Receiving HPV Vaccination, CDC Says

Too Few Teens Receiving HPV Vaccination, CDC Says

Newsy (July 24, 2014) The Centers for Disease Control and Prevention is blaming doctors for the low number of children being vaccinated for HPV. Video provided by Newsy
Powered by NewsLook.com
New Painkiller Designed To Discourage Abuse: Will It Work?

New Painkiller Designed To Discourage Abuse: Will It Work?

Newsy (July 24, 2014) The FDA approved Targiniq ER on Wednesday, a painkiller designed to keep users from abusing it. Like any new medication, however, it has doubters. Video provided by Newsy
Powered by NewsLook.com
Doctor At Forefront Of Fighting Ebola Outbreak Gets Ebola

Doctor At Forefront Of Fighting Ebola Outbreak Gets Ebola

Newsy (July 24, 2014) Sheik Umar Khan has treated many of the people infected in the Ebola outbreak, and now he's become one of them. 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