The Stem Cell Niches
Stem cells can be found in specific regions in the body. These specific areas are what is known as the Niches and they have a few important roles. In this article, I will go over the main points highlighting the importance of these specific areas.
What Are They?
Before answering the question of what stem cell niches are, it is important to define first what a stem cell can do. It actually has a few useful abilities. Number one, it has the ability to proliferate into many undifferentiated or specialized cells depending on the current need. Number two, it also has the ability to turn into specialized cells or just about any cell type that is found in the body.
With that being said, stem cell niches are just areas in the body where specific stem cell types reside. An example of this would be the bone marrow. Whenever you extract your bone marrow for its stem cells, it would still turn into bone marrow stem cells when they’re transplanted back into the system.
Aside from being a region which houses specific types of stem cells, it also has two specific functions. One, it provides a suitable environment for the stem cell to proliferate and two, it controls the stem cells from over-producing. To understand how they do that, it is important to know how it is controlled in the first place.
To this day, it is still unclear which cells control the niches, but a team of researchers led by Gedas Greicius and Professor David Virshup from the Duke-NUS Medical School, have found that two cells- the Wnts and the RSPO3, are responsible for maintaining stem cell niches.
The Controlling Cells
Virshup’s team found that in mice, the area that is known as the “subepithelial myofibroblast” is one of the sources of the Wnt and the RSPO3.
If the niche is not able to produce the former, the mice will not have the ability to develop their own adult intestines. If the area is not able to produce the R-Spondin (or the latter), the mice do not have the ability to repair their intestines in the event that it gets damaged.
They’ve concluded that there are indeed some cells that are responsible for maintaining stem cell niches. Their study justifies that the “controlling cells” work in tandem not only for the stem cells to proliferate, but also to limit their cell division as well.
Greicius and Virshup are still going to undergo the same tests, only this time, they will move up the food chain until they study humans in their final research.
However, this current study provides the notion that there are indeed some cells that maintain and regulate stem cell niches. No wonder there are specific regions where most stem cells reside.
The researchers are still finalizing if the Wnts and the RSPO3 are also found in other organisms and most importantly if it is found in humans as well. Also, they want to know if these cells (if they are present in the body) can also stimulate the same maintenance and repair mechanisms much the same way as what the mice studies have suggested.