Scar Tissue Control for Implants

Design prevents buildup of scar tissue around medical implants

A new device, which doesn’t rely on immunosuppressing drugs, may assist efforts to develop an artificial pancreas to treat diabetes.

Anne Trafton | MIT News Office,  Publication Date:August 5, 2022

Implantable devices that release insulin into the body hold promise as an alternative way to treat diabetes without insulin injections or cannula insertions. However, one obstacle that has prevented their use so far is that the immune system attacks them after implantation, forming a thick layer of scar tissue that blocks insulin release.

This phenomenon, known as the foreign body response, can also interfere with many other types of implantable medical devices. However, a team of MIT engineers and collaborators has now devised a way to overcome this response. In a study of mice, they showed that when they incorporated mechanical actuation into a soft robotic device, the device remained functional for much longer than a typical drug-delivery implant.

The device is repeatedly inflated and deflated for five minutes every 12 hours, and this mechanical deflection prevents immune cells from accumulating around the device, the researchers found.

“We’re using this type of motion to extend the lifetime and the efficacy of these implanted reservoirs that can deliver drugs like insulin, and we think this platform can be extended beyond this application,” says Ellen Roche, the Latham Family Career Development Associate Professor of Mechanical Engineering and a member of MIT’s Institute for Medical Engineering and Science.

Among other possible applications, the researchers now plan to see if they can use the device to deliver pancreatic islet cells that could act as an “bioartificial pancreas” to help treat diabetes.

Roche is the co-senior author of the study, with Eimear Dolan, a former postdoc in her lab who is now a faculty member at the National University of Ireland at Galway. Garry Duffy, also a professor at NUI Galway, is a key collaborator on the work, which appears in Nature Communications. MIT postdocs William Whyte and Debkalpa Goswami, and visiting scholar Sophie Wang, are the lead authors of the paper. ... '