Scientists found special types of bone stem cells in the body

On November 6th, medical stem cells are very valuable because they can heal many types of bone damage, but many researchers have found bone stem cells because they don't know the shape of bone stem cells or their existence. Recently, one In a research report published in the international journal Nature, scientists from the University of Michigan identified a class of bone stem cells by studying the epiphyseal growth plate. The epiphyseal growth plate is a special type. Cartilage tissue, which is an important driver of bone growth.

Researcher Noriaki Ono said that it is very meaningful to find bone stem cells in the quiescent region, because researchers generally believe that stem cells are often at rest until they are needed. To find this particular type of stem cell, researchers use fluorescent proteins to label specific cell populations in the mouse's body, and then track the fate changes of these cells over time, in this way, researchers can study these cells. Behavioral changes throughout the life cycle in the natural state (not just in the culture dish).

These researchers found that the special cells of the bone to meet the criteria of stem cells, since it has several important properties, i.e., can be transformed into cells producing cartilage and bone, also can be converted into specific cells to support production of blood cells. Researchers believe that this cell may be just one of the bone stem cells; understanding the important functions these stem cells play in the growth plate may help the researchers explain why certain patients suffer from special types of skeletal malformations or other bone diseases .

The epiphyseal growth plate consists of multiple layers, and the uppermost layer is a resting area. Previously, researchers thought that cells in the resting region did not divide, but in this study, the researchers found that some of the resting regions Cells are able to wake up and produce rapidly dividing chondrocytes that produce beautiful "columnar" structures and maintain bone growth. Some cells in the resting zone can extend from the top of the growth plate to the bottom, and some even enter the medullary cavity through the growth plate to form osteoblasts and bone marrow stromal cells, thereby supporting blood cell growth.

Finally, the researcher Noriaki said that the cells in the resting area are not what they thought were doing nothing. They are actually very hardworking cells that will occasionally wake up to make the chondrocytes needed by the body. Scientists have been thinking of bone growth for many years. The chondrocytes at the bottom of the plate will die, but the study has provided clear evidence that these cells can survive and continue to make bone.

Original source: Koji Mizuhashi, Wanida Ono, Yuki Matsushita, et al. Resting zone of the growth plate houses a unique class of skeletal stem cells, Nature (2018). DOI: 10.1038/s41586-018-0662-5