The demand for orthopaedic biomaterials is growing in line with ageing populations. Bone substitutes that encourage the development of blood vessels are at the top of research priorities.
Bone fracture non-union when the normal process of bone healing is interrupted is a serious complication. Non- or non-delayed union fracture often requires a synthetic bone substitute but those available currently neglect the formation of new blood vessels (angiogenesis).
Pro-angiogenic potential is critical for effective healing and is regulated by mechanical and chemical factors. Important mechanical components are the sheer stress caused by blood flow itself and extracellular stiffness.
The EU-funded ‘Vascular bone’ (VB) project focused on filling this gap and has investigated stiffness and angiogenesis to develop a pro-angiogenic bone substitute. Blood supply depends on the lining of blood vessels called endothelial cells (ECs). Testing the effects of low and high stiffness substrates on tube formation of ECs revealed that high stiffness corresponds to actual bone rigidity.
The scientists used a co-culture system without cell-to-cell contact to test the extent of differentiation of human mesenchymal stem cells into osteoblast-like cells. The most striking result was the discovery that stiffness modulated protein activity as well as growth factor expression.
VB project results have expanded the knowledge on the environment required for effective bone healing. Most of the beneficiaries will be elderly people at very high risk of fracture as a result of osteoporosis. However, there is a high demand in orthopaedic surgery for effective bone substitutes to treat the rising challenge of non-union fractures.
CORDIS, cordis.europa.eu
© European Union, 1994–2020
