​New material improves treatment of complex bone infections

Researchers in Ireland have combined antimicrobial implants and gene therapies to develop a new surgical solution with the potential to improve the treatment of complex bone infections.

When implanted on an injured or infected bone, the material – developed by a team at RCSI University of Medicine and Health Sciences and Advanced Materials and Bioengineering Research Centre (AMBER) - speeds up bone healing and reduces the risk of infections without the need for antibiotics. Their work is detailed in Advanced Materials.

Standard clinical treatment for infected bones, including several weeks with antibiotics and often removal of the infected portion of bone tissue, can be slow. Furthermore, around half of bone infections are caused by MRSA, which is resistant to antibiotics, and prolonged antibiotic treatment increases the risk of infections becoming tolerant to available treatments.

To help patients to heal, researchers at RCSI created a material from a substance that is similar to bone. The scaffold-like structure of this material means that when it is implanted onto injured or diseased bone, it encourages the bone to regrow.

MORE FROM MEDICAL & HEALTHCARE

The RCSI researchers infused the scaffold with nanoparticles of copper, which are known to kill the bacterium that causes most bone infections. They also incorporated a specific genetic molecule, an inhibitor of microRNA-138, into the scaffold to stimulate the formation of new bone at the site where the material is implanted.

Preclinical lab tests showed that the implanted scaffolds with the copper nanoparticles and microRNA could stimulate bone regrowth in a fortnight, and that the scaffold stopped 80 per cent of potentially harmful bacteria from attaching to the site.

They also saw that the implants stimulated a good blood supply to cells on the scaffold which is crucial for the health and viability of the newly formed bone.

“Overall, we combined the power of antimicrobial implants and gene therapies, leading to a holistic system which repairs bone and prevents infection,” said first author of the study, Dr Joanna Sadowska, a Marie Skłodowska-Curie Postdoctoral Fellow at the RCSI Tissue Engineering Research Group (TERG). “This makes a significant step forward in treating complex bone injuries, and the timescale we saw in our preclinical studies suggest our approach could revolutionise treatment times for patients in the future.”