Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Using geometry, researchers coax human embryonic stem cells to organize themselves

01.07.2014

About seven days after conception, something remarkable occurs in the clump of cells that will eventually become a new human being. They start to specialize. They take on characteristics that begin to hint at their ultimate fate as part of the skin, brain, muscle or any of the roughly 200 cell types that exist in people, and they start to form distinct layers.

Although scientists have studied this process in animals, and have tried to coax human embryonic stem cells into taking shape by flooding them with chemical signals, until now the process has not been successfully replicated in the lab. But researchers led by Ali Brivanlou, Robert and Harriet Heilbrunn Professor and head of the Laboratory of Stem Cell Biology and Molecular Embryology at The Rockefeller University, have done it, and it turns out that the missing ingredient is geometrical, not chemical.


Growth pattern. Forty-two hours after they began to differentiate, embryonic cells are clearly segregating into endoderm (red), mesoderm (blue) and ectoderm (black). Researchers say the key to achieving this patterning in culture is confining the colonies geometrically.

“Understanding what happens in this moment, when individual members of this mass of embryonic stem cells begin to specialize for the very first time and organize themselves into layers, will be a key to harnessing the promise of regenerative medicine,” Brivanlou says. “It brings us closer to the possibility of replacement organs grown in petri dishes and wounds that can be swiftly healed.”

In the uterus, human embryonic stem cells receive chemical cues from the surrounding tissue that signal them to begin forming layers — a process called gastrulation. Cells in the center begin to form ectoderm, the brain and skin of the embryo, while those migrating to the outside become mesoderm and endoderm, destined to become muscle and blood and many of the major organs, respectively.

Brivanlou and his colleagues, including postdocs Aryeh Warmflash and Benoit Sorre as well as Eric Siggia, Viola Ward Brinning and Elbert Calhoun Brinning Professor and head of the Laboratory of Theoretical Condensed Matter Physics, confined human embryonic stem cells originally derived at Rockefeller to tiny circular patterns on glass plates that had been chemically treated to form “micropatterns” that prevent the colonies from expanding outside a specific radius. When the researchers introduced chemical signals spurring the cells to begin gastrulation, they found the colonies that were geometrically confined in this way proceeded to form endoderm, mesoderm and ectoderm and began to organize themselves just as they would have under natural conditions. Cells that were not confined did not.

By monitoring specific molecular pathways the human cells use to communicate with one another to form patterns during gastrulation — something that was not previously possible because of the lack of a suitable laboratory model — the researchers also learned how specific inhibitory signals generated in response to the initial chemical cues function to prevent the cells within a colony from all following the same developmental path.

The research was published June 29 in Nature Methods.

“At the fundamental level, what we have developed is a new model to explore how human embryonic stem cells first differentiate into separate populations with a very reproducible spatial order just as in an embryo,” says Warmflash. “We can now follow individual cells in real time in order to find out what makes them specialize, and we can begin to ask questions about the underlying genetics of this process.”

The research also has direct implications for biologists working to create “pure” populations of specific cells, or engineered tissues consisting of multiple cell types, for use in medical treatments. “These cells have a powerful intrinsic tendency to form patterns as they develop,” Warmflash says. “Varying the geometry of the colonies may turn out to be an important tool that can be used to guide stem cells to form specific cell types or tissues.”

Zach Veilleux | Eurek Alert!
Further information:
http://newswire.rockefeller.edu/2014/06/30/using-geometry-researchers-coax-human-embryonic-stem-cells-to-organize-themselves/

Further reports about: Cells Embryology Rockefeller colonies geometry populations replacement signals

More articles from Life Sciences:

nachricht Could this protein protect people against coronary artery disease?
17.11.2017 | University of North Carolina Health Care

nachricht Microbial resident enables beetles to feed on a leafy diet
17.11.2017 | Max-Planck-Institut für chemische Ökologie

All articles from Life Sciences >>>

The most recent press releases about innovation >>>

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

Im Focus: A “cosmic snake” reveals the structure of remote galaxies

The formation of stars in distant galaxies is still largely unexplored. For the first time, astron-omers at the University of Geneva have now been able to closely observe a star system six billion light-years away. In doing so, they are confirming earlier simulations made by the University of Zurich. One special effect is made possible by the multiple reflections of images that run through the cosmos like a snake.

Today, astronomers have a pretty accurate idea of how stars were formed in the recent cosmic past. But do these laws also apply to older galaxies? For around a...

Im Focus: Visual intelligence is not the same as IQ

Just because someone is smart and well-motivated doesn't mean he or she can learn the visual skills needed to excel at tasks like matching fingerprints, interpreting medical X-rays, keeping track of aircraft on radar displays or forensic face matching.

That is the implication of a new study which shows for the first time that there is a broad range of differences in people's visual ability and that these...

Im Focus: Novel Nano-CT device creates high-resolution 3D-X-rays of tiny velvet worm legs

Computer Tomography (CT) is a standard procedure in hospitals, but so far, the technology has not been suitable for imaging extremely small objects. In PNAS, a team from the Technical University of Munich (TUM) describes a Nano-CT device that creates three-dimensional x-ray images at resolutions up to 100 nanometers. The first test application: Together with colleagues from the University of Kassel and Helmholtz-Zentrum Geesthacht the researchers analyzed the locomotory system of a velvet worm.

During a CT analysis, the object under investigation is x-rayed and a detector measures the respective amount of radiation absorbed from various angles....

Im Focus: Researchers Develop Data Bus for Quantum Computer

The quantum world is fragile; error correction codes are needed to protect the information stored in a quantum object from the deteriorating effects of noise. Quantum physicists in Innsbruck have developed a protocol to pass quantum information between differently encoded building blocks of a future quantum computer, such as processors and memories. Scientists may use this protocol in the future to build a data bus for quantum computers. The researchers have published their work in the journal Nature Communications.

Future quantum computers will be able to solve problems where conventional computers fail today. We are still far away from any large-scale implementation,...

Im Focus: Wrinkles give heat a jolt in pillared graphene

Rice University researchers test 3-D carbon nanostructures' thermal transport abilities

Pillared graphene would transfer heat better if the theoretical material had a few asymmetric junctions that caused wrinkles, according to Rice University...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

Ecology Across Borders: International conference brings together 1,500 ecologists

15.11.2017 | Event News

Road into laboratory: Users discuss biaxial fatigue-testing for car and truck wheel

15.11.2017 | Event News

#Berlin5GWeek: The right network for Industry 4.0

30.10.2017 | Event News

 
Latest News

NASA detects solar flare pulses at Sun and Earth

17.11.2017 | Physics and Astronomy

NIST scientists discover how to switch liver cancer cell growth from 2-D to 3-D structures

17.11.2017 | Health and Medicine

The importance of biodiversity in forests could increase due to climate change

17.11.2017 | Studies and Analyses

VideoLinks
B2B-VideoLinks
More VideoLinks >>>