Stem Cell-Extracted Proteins Promote Bone Regrowth

Scientists from the Gladstone Institutes have found a new technique to regrow bone by using the protein signals produced by stem cells. This new technology could potentially help treat victims who have experienced major trauma to a limb, such as soldiers wounded in combat or casualties of a natural disaster. This new protocol improves older therapies by providing a sustainable source for fresh tissue that also reduces the risk of tumor formation that can arise with stem cell transplants.

This study was published in a journal called Scientific Reports, and it is the first study that successfully extracted bone-producing growth factors from stem cells and showed that these proteins are sufficient to create new bone. This stem cell-based approach was as effective as the current standard treatment in terms of the amount of bone created.

“This proof-of-principle work establishes a novel bone formation therapy that exploits the regenerative potential of stem cells,” says senior author Todd McDevitt, PhD, a senior investigator at the Gladstone Institutes. “With this technique, we can produce new tissue that is completely stem cell-derived and that performs similarly with the gold standard in the field.”

Rather than using stem cells, the Gladstone scientists extracted the proteins that the stem cells secrete, such as a protein called bone morphogenetic protein (BMP). By extracting these proteins, they hoped to harness their regenerative power. McDevitt and his colleagues treated stem cells with a chemical that helped drove them to begin to differentiate into early bone cells. Then they analyzed the secreted factors produced by these cells that signal to other cells to regenerate new tissue. Afterwards, they took these isolated proteins and injected then into mouse muscle tissue to facilitate new bone growth.

Currently, laboratory technicians grind up old bones and extract the available proteins and growth factors that can induce the growth of new bone. Unfortunately, this approach relies on bones taken from cadavers, which are highly variable when it comes to the quality of the available tissue and how much of the necessary signals they still produce. Also, cadaver tissue is not always available.

“These limitations motivate the need for more consistent and reproducible source material for tissue regeneration,” says Dr. McDevitt, who conducted the research while he was a professor at the Georgia Institute of Technology. “As a renewable resource that is both scalable and consistent in manufacturing, pluripotent stem cells are an ideal solution.”