Scientists Unlock Secrets of Human Embryonic Stem Cell Formation with Geometry

Stem cells are extraordinary. They have the potential to change and take on the characteristics of any type of cell in the body. While scientists have attempted to coax human embryonic stem cells into taking specific shapes, though, they've so far been unsuccessful. Now, though, they have managed the process with the help of some geometry.

"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," said Ali Brivanlou, one of the researchers, in a news release. "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. This essentially tells the cells to form layers in a process called gastrulation. Cells in the center form the ectoderm while those on the outside become the mesoderm and endoderm, which are destined to become muscle, blood and many major organs.

Now it turns that in order to influence the creation of these cells, they need a little help with formation. The researchers confined human embryonic stem cells to tiny circular patterns on glass place that had been chemically treated for form "micropatterns" that prevented the colonies from expanding outside a specific radius.  When the researchers introduced chemical signals spurring the cells, they found that the colonies that were confined proceeded to develop in the same way as they would have under natural conditions.

"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," said Aryeh Warmflash, one of the researchers, in a news release. "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 findings are published in the journal Nature Methods.