There’s a time to grow and a time to heal—and the cells that make up our bone and cartilage have impeccable timing. During childhood and adolescence, these cells work to grow the bones longer and stronger. Once we’ve reached adulthood, they shift focus to repair and healing.
This is part of why children with bone deformities are often forced to wait until adulthood—until their bones stop growing—before their condition can be corrected.
Another part of the reason behind the agonizing wait is that scientists still don’t know exactly how this transition in bone cells, from a focus on growing to a focus on healing, even happens.
But new research out of the University of Michigan (UM) is well on its way to changing that.
In findings published today in Nature Cell Biology, Noriaki Ono (a UM assistant professor of dentistry) and his team announce the discovery of a subset of cartilage-making cells that take on new duties during the transition from adolescence into adulthood.
Previously, scientists had thought that these cartilage-making cells, known as chondrocytes, die once the bones stopped growing. But these new findings by Ono and his team showed that is not the case—not all chondrocytes bite the dust. Instead, they literally transform themselves from growing bone, to healing it.
The fact that some chondrocytes persist through to adulthood may mean that they can be selectively targeted to correct bone deformities in younger patients. As Ono explained in more detail:
“Up until now, the cells that drive this bone growth have not been understood very well. As an orthodontist myself, I have special interest in this aspect, especially for finding a cure for severe bone deformities in the faces of children. If we can find a way to make bones that continue to grow alongside the child, maybe we should be able to put these pieces of growing bones back into children and make their faces look much better than they do.”