Tendon stem cells can be harnessed to improve tendon healing

Washington: A new research has revealed the existence of tendon stem cells that can potentially be harnessed to improve tendon healing and even to avoid surgery. The research was led by Carnegie's Chen-Ming Fan and published in the journal of Nature Cell Biology. Fan explained: "Tendons are the connective tissue that tethers our muscles to our bones; they improve our stability and facilitate the transfer of force that allows us to move. But they are also particularly susceptible to injury and damage."

Unfortunately, once tendons are injured, they rarely fully recover, which can result in limited mobility and require long-term pain management or even surgery. The culprit is fibrous scars, which disrupt the tissue structure of the tendon. Working with Carnegie's Tyler Harvey and Sara Flamenco, Fan revealed that all of the cell types present in the Patellar tendon found below the kneecap, including previously undefined tendon stem cells.

According to lead author Harvey, "Because tendon injuries rarely heal completely, it was thought that tendon stem cells might not exist, many searched for them to no avail, but our work defined them for the first time." Surprisingly, the team's research showed that both fibrous scar tissue cells and tendon stem cells originate in the same space -- the protective cells that surround a tendon. These tendon stem cells are part of a competitive system with precursors of fibrous scars, which explains why tendon healing is such a challenge.

Fan added: "Tendon stem cells exist, but they must out-compete the scar tissue precursors in order to prevent the formation of difficult, fibrous scars, finding a therapeutic way to block the scar-forming cells and enhance the tendon stem cells could be a game-changer when it comes to treating tendon injuries."