Electricity reprograms immune cells to speed up recovery

This discovery points to a promising new treatment strategy, and the research team is continuing to study the mechanisms behind this effect.

What Macrophages Do

Macrophages are white blood cells that play a central role in defending the body. They move throughout tissues searching for harmful microbes and viruses, clearing away damaged or dead cells, and activating other parts of the immune system when needed.

However, when macrophages overreact, they can trigger excessive inflammation that damages tissues instead of repairing them. This runaway inflammation is a hallmark of many diseases, making macrophage regulation a key target for improving recovery and reducing chronic conditions.

Testing Electricity's Effect on Immune Cells

In the new study, published in Cell Reports Physical Science, the Trinity researchers worked with macrophages taken from healthy blood donors through the Irish Blood Transfusion Board at St James's Hospital. The team placed the cells in a specialized bioreactor that allowed them to apply controlled electrical stimulation and observe the biological effects.

The results were striking. Electrical stimulation shifted the macrophages toward an anti-inflammatory state that promotes tissue repair. The scientists observed lower activity in inflammatory signaling markers, increased expression of genes responsible for forming new blood vessels (essential for tissue growth), and enhanced recruitment of stem cells to wounds (another vital component of the healing process).

Turning Down Inflammation, Turning Up Repair

"We have known for a very long time that the immune system is vital for repairing damage in our body and that macrophages play a central role in fighting infection and guiding tissue repair," said Dr. Sinead O'Rourke, Research Fellow in Trinity's School of Biochemistry and Immunology and first author of the study.

"As a result, many scientists are exploring ways to 'reprogram' macrophages to encourage faster, more effective healing in disease and to limit the unwanted side-effects that come with overly aggressive inflammation. And while there is growing evidence that electrical stimulation may help control how different cells behave during wound healing, very little was known about how it affects human macrophages prior to this work."

A Promising Path for Future Therapies

"We are really excited by the findings. Not only does this study show for the first time that electrical stimulation can shift human macrophages to suppress inflammation, we have also demonstrated increased ability of macrophages to repair tissue, supporting electrical stimulation as an exciting new therapy to boost the body's own repair processes in a huge range of different injury and disease situations."

The research team, led by Professors Aisling Dunne (School of Biochemistry and Immunology) and Michael Monaghan (School of Engineering), emphasized the potential of this approach. Because the study used human blood cells, the findings are directly relevant to clinical applications. Electrical stimulation is also relatively safe and easy to implement compared to many therapeutic methods, making it an attractive candidate for a variety of medical uses.

Next Steps and Expanding Potential

Professor Monaghan added: "Among the future steps are to explore more advanced regimes of electrical stimulation to generate more precise and prolonged effects on inflammatory cells and to explore new materials and modalities of delivering electric fields. This concept has yielded compelling effects in vitro and has huge potential in a wide range of inflammatory diseases."

The research marks an important step toward developing electricity-based therapies that could one day help the body repair itself more effectively and safely.