A new study has found that certain cells within our bones may alter their usual function and begin to act like stem cells to help bones heal after an injury. In the future, scientists may be able to harness the ability of these cells to regenerate tissue in order to study and treat diseases and injuries.
Prior to the recent study, it was believed that only skeletal stem cells could create new bone, and help to grow or to heal existing bone after an injury. Stem cells are already used in regenerative medicine in areas such as bone marrow transplantation, and many scientists believe that the ability of stem cells to repair and renew damaged tissue will lead to increased understanding and ability to treat a wide range of diseases and disorders.
Skeletal stem cells are few in number and so cell turnover in adult bones is thought to be slow compared with other parts of the body. The relative rarity of skeletal stem cells also makes it more difficult for their regenerative abilities to be used medically.
Researchers at the University of Michigan have recently undertaken a study using mice to investigate bone cell reaction to injury. The findings, published in the journal Nature Communications, indicated that it is not only skeletal stem cells that work to heal damaged bone, as previously believed.
Cells within the bone known as ‘CAR cells’, which usually perform other tasks such as helping to regulate blood cells, responded to bone injury in the study and began acting to regenerate the damaged tissue. This only happened where injury occurred; in the healthy bones, these cells did nothing to aid growth, which was left to the skeletal stem cells.
CAR cells are far more numerous than stem cells and therefore provide a much faster level of bone regeneration than the stem cells alone could achieve.
The Michigan study was conducted on mice, so further research will be required to apply these findings to human cells. However, these results do suggest that the body may have the ability to enlist cells other than stem cells to assist with damage-repair when needed, which illustrates that human cells may be more adaptable than previously believed. Scientists may be able to apply these findings by transforming other cells, which are readily available, into skeletal stem cells. If successful, this would allow for more in-depth research and potentially new and better treatments for patients with bone disorders or injuries.