Stem cells responsible for forming bone and cartilage

Although performed in mice, the study indicates that transfer to humans should not be complex, since they share many of the major genes used in mouse skeletal system

Stem cells are responsible for making bone, cartilage and stroma, an essential component of the bone marrow – have just been identified by a team of researchers from Stanford University (USA). Although it has-been found in mice, the finding published in “Cell” may serve to advance the development of treatments for bone disorders such as, bone fractures, brittle bones, osteosarcoma, etc.

The absence of cartilage caused by an injury, is a common problem for orthopedic surgeons, recognizes Michael Longaker, lead author of the article. Now, thanks to this research it is possible to make new stem cell skeleton of the patient’s own tissues and use them to grow new cartilage.

The researchers worked first in groups of cells that divide rapidly at the ends of the bones of mouse and later saw that all parties could form bone: bone, cartilage and stroma, the spongy tissue in the center of the bones that helps hematopoietic stem cells to become blood and immune cells. Then identified a unique cell type could form the skeleton. Experts went much further, mapping the evolutionary tree of skeletal stem cells to accurately track how they transform into intermediate progenitor cells and finally in each type of skeletal tissue. Mapping the tree allowed scientists to understand in depth all the genetic switches that have to be activated to give parents more specific and specialized cells.

With this information, the researchers were able to find factors that, when provided in the right quantity at the right time, direct the development of skeletal stem cells into bone cells, cartilage or stroma. If this results in humans, then researchers would have a way to isolate stem cells and rescue skeletal cartilage wear or aging, repair bone fractures that are not healing and renewing the bone marrow niche in people where is corrupt.

The scientists also found how to manufacture skeletal stem cells from fat cells or muscle. The possibility of reprogramming mature fat cells directly into skeletal stem cells through the application of specific signals was an interesting and quite unexpected event. In his view, this raises intriguing possibilities for future therapies.

Meanwhile, other therapies can be performed in a single surgical session. The number of skeletal stem cells decreases dramatically with age, so bone fractures or dental implants do not heal very well in the elderly because new bone does not grow easily. But maybe you can take fat from the patient’s body during surgery, combined with these reprogramming factors right there in the operating room, and immediately transplanted new skeletal stem cells in the patient. But do not forget that the work has been carried out in mice. Research should help to find the stem cells of the human skeleton and decode the chemical language used to direct its development.