Can we change how the body reacts to medical implants?

12 Oct 2022

Dr Eimear Dolan. Image: University of Galway

Dr Eimear Dolan and her team are working on a way to prevent the build-up of scar tissue on medical devices and improve drug delivery.

Medical devices have seen huge advancements in recent years and a focus in this sector is implantable drug delivery devices.

For example, there are devices that can release insulin into the body over long periods of time as an alternative way to treat diabetes without the need for insulin injections.

However, while emerging tech is advancing at a rapid pace, our own bodies don’t always see these devices as a welcome addition.

The immune system can attack these devices after implantation in an attempt to protect the body from foreign objects. A thick layer of scar tissue can form around the implant, blocking the release of insulin.

This process, known as the foreign body response, can interfere with many other types of medical implants that rely on a close interaction with the body, leading to premature device failure.

However, Dr Eimear Dolan along with a team of researchers from University of Galway and MIT are working on a way to address this problem.

‘The body will adapt and remodel, especially if we intervene by implanting a device’

“Our team have incorporated mechanical actuation into our design, which enables small and regular movements of the implanted device,” she said.

“We showed that just by moving the device every 12 hours, the device remained functional after eight weeks of implantation and was as good as a freshly implanted device. It also showed that this type of motion modulates how immune cells respond to the implant, which extends the lifetime and efficacy of the implant.”

Dolan is no stranger to the medical device field. An associate professor in biomedical engineering at University of Galway, she is well-versed in the power of soft robotics in the medtech space.

In 2019, she received almost €130,000 in funding from Science Foundation Ireland for her ImmunoCell project, which aimed to create an implantable cell reservoir device for the replenishable delivery of natural killer cells for ovarian cancer treatment.

The following year, she was included among the ‘visionaries’ in MIT Technology Review’s Innovator Under 35 list.

Dolan said Galway is a great place to be for biomedical engineering. “We have a unique ecosystem here for innovation,” she said.

“I have been very lucky that I have had very supportive colleagues and mentors throughout my career so far. We have a great community in biomedical engineering in Ireland and internationally.”

Preventing scar tissue build-up

In her most recent research, which was a collaboration between University of Galway and MIT and was published in Nature Communications, the team found that mechanical actuation clears away the immune cells that initiate the process that leads to scar tissue formation.

While scar tissue did eventually form, the research showed that its structure was more highly aligned than if the device was static, which the researchers believe may help drug molecules to pass through the tissue.

“There are always lots of technical challenges to be overcome on projects like this. We had an excellent team of researchers working on this study who really were a pleasure to work with,” Dolan told

“One thing that I find really interesting about biomedical engineering is that the body will adapt and remodel, especially if we intervene by implanting a device, for example. So we need to understand the behaviour of the implant over time but also the changes in the body because of this implant. Decoupling these two things is often challenging!”

With backing from the Enterprise Ireland Commercialisation Fund, Dolan and her team are now developing fully implantable and partially implantable versions of this technology with the aim of improving insulin delivery for people with diabetes.

She said she’s hopeful that her team’s technology can be applicable to other devices that fail prematurely due to the foreign body response.

“I think our approach could be implemented to improve the performance of a range of implantable drug delivery devices – from insulin to cancer therapy delivery.”

In terms of what the future holds for biomedical engineering, Dolan said the biggest trend is how data driven everything has become.

“Future medical implants will have more sensors incorporated, which can give real-time measurements of the device performance and responses of the nearby tissue over time.”

10 things you need to know direct to your inbox every weekday. Sign up for the Daily Brief, Silicon Republic’s digest of essential sci-tech news.

Jenny Darmody is the editor of Silicon Republic