Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Shaping up: Controlling a stem cell's form can determine its fate

14.09.2011
"Form follows function!" was the credo of early 20th century architects making design choices based on the intended use of the structure.

Cell biologists may be turning that on its head. New research* by a team working at the National Institute of Standards and Technology (NIST) reinforces the idea that stem cells can be induced to develop into specific types of cells solely by controlling their shape. The results may be important to the design of materials to induce the regeneration of lost or damaged tissues in the body.


Bone-like cell growth on nanofibers: confocal microscope images detail the growth of a human bone marrow stromal cell (actin filaments in the cell "skeleton" are stained orange) on a nanofiber scaffold (green). The structure of thin fibers encourages stem cells to develop into the elongated, branched form characteristic of mature bone cells. Credit: Tison, Simon/NIST

Tissue engineering seeks to repair or re-grow damaged body tissues, often using some form of stem cells. Stem cells are basic repair units in the body that have the ability to develop into any of several different forms. The NIST experiments looked at primary human bone marrow stromal cells, adult stem cells that can be isolated from bone marrow and can "differentiate" into bone, fat or cartilage cells, depending.

"Depending on what?" is one of the key questions in tissue engineering. How do you ensure that the stem cells turn into the type you need? Chemical cues have been known to work in cases where researchers have identified the proper additives—a hormone in the case of bone cells. Other research has suggested that cell differentiation on flat surfaces can be controlled by patterning the surface to restrict the locations where growing cells can attach themselves.

The experiments at NIST are believed to be the first head-to-head comparison of five popular tissue scaffold designs to examine the effect of architecture alone on bone marrow cells without adding any biochemical supplements other than cell growth medium. The scaffolds, made of a biocompatible polymer, are meant to provide a temporary implant that gives cells a firm structure on which to grow and ultimately rebuild tissue. The experiment included structures made by leaching and foaming processes (resulting in microscopic structures looking like clumps of insect-eaten lettuce), freeform fabrication (like microscopic rods stacked in a crisscross pattern) and electrospun nanofibers (a random nest of thin fibers). Bone marrow stromal cells were cultured on each, then analyzed to see which were most effective at creating deposits of calcium—a telltale of bone cell activity. Microarray analysis also was used to determine patterns of gene expression for the cultured cells.

The results show that the stem cells will differentiate quite efficiently on the nanofiber scaffolds—even without any hormone additives—but not so on the other architectures. The distinction, says NIST biologist Carl Simon, Jr., seems to be shape. Mature bone cells are characteristically long and stringy with several extended branches. Of the five different scaffolds, only the nanofiber one, in effect, forces the cells to a similar shape, long and branched, as they try to find anchor points. Being in the shape of a bone cell seems to induce the cells to activate the genes that ultimately produce bone tissue.

"This suggests that a good strategy to design future scaffolds would be to take into account what shape you want to put the cells in," says Simon, adding, "That's kind of a tall order though, you'd have to understand a lot of stuff: how cell morphology influences cell behavior, and then how the three-dimensional structure can be used to control it." Despite the research still to be done on this method, the ability to physically direct cell differentiation by shape alone potentially would be simpler, cheaper and possibly safer than using biochemical supplements, he says.

The work was supported in part by the National Institute of Dental and Craniofacial Research, National Institutes of Health.

* G. Kumar, C.K. Tison, K. Chatterjee, P.S. Pine, J.H. McDaniel, M.L. Salit, M.F. Young and C.G. Simon, Jr. The determination of stem cell fate by 3D scaffold structures through the control of cell shape. Biomaterials (2011), doi:10.1016/j.biomaterials.2011.08.054.

Michael Baum | EurekAlert!
Further information:
http://www.nist.gov

More articles from Life Sciences:

nachricht The balancing act: An enzyme that links endocytosis to membrane recycling
07.12.2016 | National Centre for Biological Sciences

nachricht Transforming plant cells from generalists to specialists
07.12.2016 | Duke University

All articles from Life Sciences >>>

The most recent press releases about innovation >>>

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

Im Focus: Significantly more productivity in USP lasers

In recent years, lasers with ultrashort pulses (USP) down to the femtosecond range have become established on an industrial scale. They could advance some applications with the much-lauded “cold ablation” – if that meant they would then achieve more throughput. A new generation of process engineering that will address this issue in particular will be discussed at the “4th UKP Workshop – Ultrafast Laser Technology” in April 2017.

Even back in the 1990s, scientists were comparing materials processing with nanosecond, picosecond and femtosesecond pulses. The result was surprising:...

Im Focus: Shape matters when light meets atom

Mapping the interaction of a single atom with a single photon may inform design of quantum devices

Have you ever wondered how you see the world? Vision is about photons of light, which are packets of energy, interacting with the atoms or molecules in what...

Im Focus: Novel silicon etching technique crafts 3-D gradient refractive index micro-optics

A multi-institutional research collaboration has created a novel approach for fabricating three-dimensional micro-optics through the shape-defined formation of porous silicon (PSi), with broad impacts in integrated optoelectronics, imaging, and photovoltaics.

Working with colleagues at Stanford and The Dow Chemical Company, researchers at the University of Illinois at Urbana-Champaign fabricated 3-D birefringent...

Im Focus: Quantum Particles Form Droplets

In experiments with magnetic atoms conducted at extremely low temperatures, scientists have demonstrated a unique phase of matter: The atoms form a new type of quantum liquid or quantum droplet state. These so called quantum droplets may preserve their form in absence of external confinement because of quantum effects. The joint team of experimental physicists from Innsbruck and theoretical physicists from Hannover report on their findings in the journal Physical Review X.

“Our Quantum droplets are in the gas phase but they still drop like a rock,” explains experimental physicist Francesca Ferlaino when talking about the...

Im Focus: MADMAX: Max Planck Institute for Physics takes up axion research

The Max Planck Institute for Physics (MPP) is opening up a new research field. A workshop from November 21 - 22, 2016 will mark the start of activities for an innovative axion experiment. Axions are still only purely hypothetical particles. Their detection could solve two fundamental problems in particle physics: What dark matter consists of and why it has not yet been possible to directly observe a CP violation for the strong interaction.

The “MADMAX” project is the MPP’s commitment to axion research. Axions are so far only a theoretical prediction and are difficult to detect: on the one hand,...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

ICTM Conference 2017: Production technology for turbomachine manufacturing of the future

16.11.2016 | Event News

Innovation Day Laser Technology – Laser Additive Manufacturing

01.11.2016 | Event News

#IC2S2: When Social Science meets Computer Science - GESIS will host the IC2S2 conference 2017

14.10.2016 | Event News

 
Latest News

NTU scientists build new ultrasound device using 3-D printing technology

07.12.2016 | Health and Medicine

The balancing act: An enzyme that links endocytosis to membrane recycling

07.12.2016 | Life Sciences

How to turn white fat brown

07.12.2016 | Health and Medicine

VideoLinks
B2B-VideoLinks
More VideoLinks >>>