Novel implant delivers tiny growth-promoting particles directly to injured nerve cells

Researchers from RCSI University of Medicine and Health Sciences have developed a novel implant that delivers tiny growth-promoting particles directly to injured nerve cells, helping them to regrow after spinal cord injury.

The study, published in the journal Bioactive Materials, shows how a 3D implant designed to mimic the structure and stiffness of the spinal cord can be combined with tiny particles engineered to carry RNA to encourage nerve cells (neurons) to grow. The work was led by researchers at RCSI's Tissue Engineering Research Group (TERG) and the Research Ireland Centre for Advanced Materials and BioEngineering Research (AMBER).

Spinal cord injuries often result in permanent paralysis because damaged neurons in the central nervous system have a very limited capacity to regrow. While biomaterial implants can provide physical support at the injury site, these cells also face molecular barriers that prevent their regrowth.

To overcome this, the team developed a multifunctional implant that not only supports regenerating tissue but also delivers RNA-based signals that encourage neurons to switch their growth mechanisms back on.

These signals target one such barrier, a gene called PTEN, which is known to suppress neuron regrowth after injury. By silencing PTEN at the injury site, the implant helps remove an internal barrier to repair in these cells.

We've created an environment that both physically and biologically re-enhances the regenerative capacity of injured neurons, which is a key requirement for restoring function after spinal cord injury. In laboratory models of spinal cord injury, neurons exposed to the RNA-activated implant showed significantly enhanced growth."

Fergal O'Brien, Deputy Vice Chancellor for Research and Innovation, Professor of Bioengineering and Regenerative Medicine and Head of RCSI TERG

The research was developed with guidance from an advisory panel supported by the Irish Rugby Football Union Charitable Trust (IRFU-CT), bringing together people living with spinal cord injury, clinicians, neuroscientists and engineers to shape research priorities and ensure relevance to patients' real-world needs.

"While this study focused on laboratory models, the next steps will to be to test the approach in vivo and explore how RNA-activated biomaterials could help bridge damaged spinal cord tissue and restore lost connections," said Dr Tara McGuire who carried out the research as a PhD student in TERG.

The study was supported by the IRFU-CT and Research Ireland with additional funding from the Anatomical Society and the Health Research Board.