Improving Bone Graft Surgeries With Better Biomaterials

Spring 2022

More than two million bone graft surgeries occur annually across the world to address defects in the bones of the skull. These wounds may be congenital or result from traumatic injury or cancer treatment, and they are difficult to address. They are usually irregularly shaped and motivate the design of implantable biomaterials that can regenerate the lost bone. A research team led by Professor Brendan Harley is working to develop these biomaterials.

Harley is the Robert W. Schaefer Professor in the Department of Chemical & Biomolecular Engineering and an affiliate of the Carl R. Woese Institute for Genomic Biology and the Cancer Center at Illinois.

“Our lab focuses on developing degradable biomaterials — also known as scaffolds — for bone and tissue repair,” said Vasiliki Kolliopoulos, a graduate student in the Harley lab. “There are many types of cells in the bone environment that contribute to healing, including stem cells that form bone and monocytes that help with the immune response.”

Here, we see the team’s electron microscope image of a mineralized collagen scaffold used to repair face and skull injuries, showing mineral crystals and collagen fibers. Color has been added to make the image easier to interpret.

A recent paper published by the Harley Lab in Materialia showed how certain sugar compounds called glycosaminoglycans influence processes important to bone regeneration. The researchers introduced three types of glycosaminoglycans into the mineralized collagen scaffold and tracked how those different sugar compounds impacted stem cell, immune cell, and endothelial cell activity.

Read the Team's Paper

“Glycosaminoglycan content of a mineralized collagen scaffold promotes mesenchymal stem cell secretion of factors to modulate angiogenesis and monocyte differentiation”

“Bone regeneration requires the growth of blood vessels and not many people have looked at how scaffold materials affect endothelial cells and how it could improve bone repair,” said Marley Dewey, a former graduate student in the Harley lab who is now a postdoc at the University of Pittsburgh.