Stem Cell Specialization is Ruled by Geometry

Researchers have long struggled to figure out how exactly embryonic stem cells develop into the specialized cell "factories" that craft human tissue and organs - a process that occurs only seven days after conception. Now, researchers from the Rockefeller University believe they finally have the answer, and it may surprise you to learn geometry has a lot to do with it.

"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," lead researcher Ali Brivanlou said in a recent statement. "It brings us closer to the possibility of replacement organs grown in petri dishes and wounds that can be swiftly healed."

Previous stem cell research has determined how to grow organs from harvested pre-specialized stem cells, often referred to as "adult stem cells." However, these lab grown organs often lack exact structure or simply carry the wrong genetic information, making them useless for transplant.

Lab stimulated pluripotent stem cells face the same trouble, boasting a high risk of rejection or contamination if used for transplantation.

However, inspiring true embryonic stem cells (ESCs) to produce the desired tissue cells could present fewer of these risks.

According to a study published in the journal Nature Methods, researchers have long known that ESCs take chemical cues to develop. However, using these cues alone, researchers have failed to successfully specialize a cell.

Brivanlou and his colleagues determined that geometric patterning also played an important role after observing ESCs originally derived at Rockefeller labs. By confining the cells to circular patterns on glass plates treated to form "micropatterns," the researchers found that the ESCs began to organize themselves just as they would under natural conditions.

The researchers hope that this discovery will help future investigations look deeper into the cell specialization process, including potential genetic influences.

The study was published in Nature Methods on June 29.