Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Bioengineers: Matrix stiffness is an essential tool in stem cell differentiation

11.08.2014

Bioengineers at the University of California, San Diego have proven that when it comes to guiding stem cells into a specific cell type, the stiffness of the extracellular matrix used to culture them really does matter.

When placed in a dish of a very stiff material, or hydrogel, most stem cells become bone-like cells. By comparison, soft materials tend to steer stem cells into soft tissues such as neurons and fat cells.


Cells grown on hydrogels of the same stiffness all display fat cell markers and deform the underlying matrix material the same way.

Credit: Adam Engler, UC San Diego Jacobs School of Engineering


Cells grown on three hydrogels of the same stiffness all display fat cell markers and deform the underlying matrix material in the same way.

Credit: Adam Engler, UC San Diego Jacobs School of Engineering

The research team, led by bioengineering professor Adam Engler, also found that a protein binding the stem cell to the hydrogel is not a factor in the differentiation of the stem cell as previously suggested. The protein layer is merely an adhesive, the team reported Aug. 10 in the advance online edition of the journal Nature Materials.

Their findings affirm Engler's prior work on the relationship between matrix stiffness and stem cell differentiations.

"What's remarkable is that you can see that the cells have made the first decisions to become bone cells, with just this one cue. That's why this is important for tissue engineering," said Engler, a professor at the UC San Diego Jacobs School of Engineering.

Engler's team, which includes bioengineering graduate student researchers Ludovic Vincent and Jessica Wen, found that the stem cell differentiation is a response to the mechanical deformation of the hydrogel from the force exerted by the cell.

In a series of experiments, the team found that this happens whether the protein tethering the cell to the matrix is tight, loose or nonexistent. To illustrate the concept, Vincent described the pores in the matrix as holes in a sponge covered with ropes of protein fibers.

Imagine that a rope is draped over a number of these holes, tethered loosely with only a few anchors or tightly with many anchors. Across multiple samples using a stiff matrix, while varying the degree of tethering, the researchers found no difference in the rate at which stem cells showed signs of turning into bone-like cells.

The team also found that the size of the pores in the matrix also had no effect on the differentiation of the stem cells as long as the stiffness of the hydrogel remained the same.

"We made the stiffness the same and changed how the protein is presented to the cells (by varying the size of the pores and tethering) and ask whether or not the cells change their behavior," Vincent said. "Do they respond only to the stiffness? Neither the tethering nor the pore size changed the cells."

"We're only giving them one cue out of dozens that are important in stem cell differentiation," said Engler. "That doesn't mean the other cues are irrelevant; they may still push the cells into a specific cell type. We have just ruled out porosity and tethering, and further emphasized stiffness in this process."

###

The paper is "Interplay of matrix stiffness and protein tethering in stem cell differentiation," by Jessica H. Wen, Ludovic G. Vincent, Alexander Fuhrmann, Yu Suk Choi, Kolin Hribar, Hermes Taylor-Weiner, Shaochen Chen and Adam J. Engler in the Departments of Bioengineering and NanoEngineering at UC San Diego Jacobs School of Engineering. Engler is also a researcher at the Sanford Consortium for Regenerative Medicine. His work is partially funded by the National Institutes of Health (DP02D006460).

Catherine Hockmuth | Eurek Alert!

Further reports about: Bioengineers Engineering Matrix bone cells fat cells hydrogel materials pores stem cells stiff stiffness

More articles from Life Sciences:

nachricht Bioenergy cropland expansion could be as bad for biodiversity as climate change
11.12.2018 | Senckenberg Forschungsinstitut und Naturmuseen

nachricht How glial cells develop in the brain from neural precursor cells
11.12.2018 | Universitätsmedizin der Johannes Gutenberg-Universität Mainz

All articles from Life Sciences >>>

The most recent press releases about innovation >>>

Die letzten 5 Focus-News des innovations-reports im Überblick:

Im Focus: Researchers develop method to transfer entire 2D circuits to any smooth surface

What if a sensor sensing a thing could be part of the thing itself? Rice University engineers believe they have a two-dimensional solution to do just that.

Rice engineers led by materials scientists Pulickel Ajayan and Jun Lou have developed a method to make atom-flat sensors that seamlessly integrate with devices...

Im Focus: Three components on one chip

Scientists at the University of Stuttgart and the Karlsruhe Institute of Technology (KIT) succeed in important further development on the way to quantum Computers.

Quantum computers one day should be able to solve certain computing problems much faster than a classical computer. One of the most promising approaches is...

Im Focus: Substitute for rare earth metal oxides

New Project SNAPSTER: Novel luminescent materials by encapsulating phosphorescent metal clusters with organic liquid crystals

Nowadays energy conversion in lighting and optoelectronic devices requires the use of rare earth oxides.

Im Focus: A bit of a stretch... material that thickens as it's pulled

Scientists have discovered the first synthetic material that becomes thicker - at the molecular level - as it is stretched.

Researchers led by Dr Devesh Mistry from the University of Leeds discovered a new non-porous material that has unique and inherent "auxetic" stretching...

Im Focus: The force of the vacuum

Scientists from the Theory Department of the Max Planck Institute for the Structure and Dynamics of Matter (MPSD) at the Center for Free-Electron Laser Science (CFEL) in Hamburg have shown through theoretical calculations and computer simulations that the force between electrons and lattice distortions in an atomically thin two-dimensional superconductor can be controlled with virtual photons. This could aid the development of new superconductors for energy-saving devices and many other technical applications.

The vacuum is not empty. It may sound like magic to laypeople but it has occupied physicists since the birth of quantum mechanics.

All Focus news of the innovation-report >>>

Anzeige

Anzeige

VideoLinks
Industry & Economy
Event News

New Plastics Economy Investor Forum - Meeting Point for Innovations

10.12.2018 | Event News

EGU 2019 meeting: Media registration now open

06.12.2018 | Event News

Expert Panel on the Future of HPC in Engineering

03.12.2018 | Event News

 
Latest News

Some brain tumors may respond to immunotherapy, new study suggests

11.12.2018 | Studies and Analyses

Researchers image atomic structure of important immune regulator

11.12.2018 | Health and Medicine

Physicists edge closer to controlling chemical reactions

11.12.2018 | Physics and Astronomy

VideoLinks
Science & Research
Overview of more VideoLinks >>>