Today, we would like to highlight a recent study in which researchers show a way to selectively accelerate bone regeneration. They have achieved this by delivering Jagged-1 to injuries instead of the bone morphogenetic proteins (BMPs) that have been traditionally used.
What is jagged-1?
Jagged-1 is an osteoinductive protein that activates the Notch signaling pathway, which regulates bone healing at the site of injury. Osteoinduction is the process by which osteogenesis is induced.
Osteoinduction involves recruiting immature cells and stimulating them to change into preosteoblasts. In a bone healing situation, such as during a fracture, the majority of bone healing depends on osteoinduction.
The new technique avoids the issues of inappropriate or excessive bone growth because, unlike BMPs, it targets osteoinductive mechanisms that are more directly associated with the regenerative process.
Testing their hypothesis
The researchers led by Kurt Hankenson, D.V.M., Ph.D., a professor of orthopedic surgery at Michigan Medicine, hypothesized for some years that by binding Jagged-1 to a biomaterial structure and delivering it to the site of injury, it could improve healing of the bone.
The published study results confirm this to be the case. Mice and rats that were given Jagged-1, applied using a wet collagen sponge, saw improvements to both femoral and skull injuries. In contrast, the rodents treated with BMPs benefited but also experienced problematic bone hypertrophy, which is also observed in humans using BMPs.
The findings of this study suggest that the use of Jagged-1 for location-specific bone injury could potentially be developed into a therapy to help people recover from fractures and broken bones.
The use of signal molecules rather than drugs to encourage tissue regeneration is likely to increase in popularity in the coming years as the process becomes increasingly refined. This study is yet another example of how researchers are exploring the use of signalling molecules produced naturally in the body as an alternative to drug approaches, which can often have unwanted side effects. It should prove interesting to see how this approach develops in the next few years.
 Youngstrom, D. W., Senos, R., Zondervan, R. L., Brodeur, J. D., Lints, A. R., Young, D. R., … & Loomes, K. M. (2017). Intraoperative delivery of the Notch ligand Jagged-1 regenerates appendicular and craniofacial bone defects. NPJ Regenerative medicine, 2(1), 32.