Research Shows Stem Cells Revert to Basic State When Confined
Posted on July 27, 2018
As the most basic building blocks of the body, stem cells have the unique ability to develop into many different types of cells. This critical factor makes stem cells the very basis on which the body is built, and the origin of all tissues and organs.
Since stem cells are so basic, they essentially act as a “blank slate” until the body sends notification for them to develop, or differentiate, into a cell needed for repair of injured or aging tissue.
In 2006, Japanese stem cell researcher Shinya Yamanaka of Kyoto University discovered that this differentiation could also occur in laboratories as a result of genetic editing, in which the stem cell is reprogrammed to act like a particular type of cell.
These reprogrammed stem cells, known as induced pluripotent stem cells, have been used in thousands of applications and research projects to advance cures for incurable diseases and other health conditions. IPSCs have also been used to grow organs and test drug therapies.
Yamanaka’s discovery was a breakthrough for stem cell research, as it shifted the source of stem cells from embryos to adult stem cells. It also significantly reduced the controversy associated with stem cells.
A new study by researchers at the National University of Singapore’s Mechanobiology Institute and the FIRC Institute of Molecular Oncology in Italy has found that mature cells can be reprogrammed into stem cells without the need for genetic editing. Instead, the study authors confined stem cells to a pre-defined space for a period.
The benefit of this approach is that it eliminates the potential negative consequences of genomic editing, such as tumors.
The Singapore study authors set out to find another way to reprogram adult stem cells using fibroblasts, a kind of cell found in muscles, tendons and other types of connective tissue.
Once the fibroblasts were confined to rectangular areas, they assumed the shape of the area. This action showed researchers that the cells had the ability to respond to their environment by measuring the space and sending that information to the cell’s nucleus.
The cells were then grown over 10 days, forming spherical clusters. The researchers then analyzed the genes of the cells in these clusters and found that genetic information that gives the fibroblasts the characteristics of muscle cells was erased by the sixth day.
At the 10-day mark, the gene expression of the cells was that of embryonic stem cells and iPSCs. The cells had been reprogrammed back into pluripotent stem cells without genetic editing.
To test their theory, the researchers then reprogrammed the cells into other cell types successfully.
The results of the test are critical for stem cell therapy and regenerative medicine because they show how mature cells behave in the geometric confines of the body.
“The results of this study could mean that if the body sustains an injury that changes the shape of a tissue or organ, mature cells in that tissue or organ could revert to their basic stem cell state,” said Dr. Joel Singer, a New York stem cell physician.
Once returned to their rudimentary state, the stem cells wait until directed by the body to differentiate into the type of tissue needed for repair.
“The stem cells wait until signaled by chemical growth factors to start developing into specific cell types. Once signaled, they differentiate and begin to regenerate,” Singer said.
These growth factors also tell the body to send oxygen, blood and nutrients to support cellular health and speed healing.
After the injury is healed, the stem cells go back to their dormant state until they are needed again.
National University of Singapore. “Researchers confine mature cells to turn them into stem cells: Confined mature cells lose their specialized characteristics by sixth day and completely transition into re-deployable stem cells by 10th day.” ScienceDaily. ScienceDaily, 10 July 2018.