A soft robotic device known as a dynamic soft reservoir can help implanted devices avoid the immune response. Source: Image courtesy of the researchers, MIT
Researchers in the U.S. and Ireland recently announced what they called a “significant breakthrough” in soft robotics that could help patients with the immune response to implanted medical devices such as breast implants, pacemakers, neural probes, glucose biosensors, and drug- and cell-delivery devices.
The implantable medical devices market is currently estimated at approximately $100 billion, with significant growth potential, as new technologies for drug delivery and health monitoring are developed. These devices are not without problems, caused in part by the body’s own immune response. These complex and unpredictable foreign-body responses impair device function and drastically limit the long-term performance and therapeutic efficacy of these devices.
One such foreign body response is fibrosis, a process whereby a dense fibrous capsule surrounds the implanted device, which can cause device failure or impede its function. Implantable medical devices have various failure rates that can be attributed to fibrosis, ranging from 30% to 50% for implantable pacemakers or 30% for mammoplasty prosthetics. In the case of biosensors or drug/cell delivery devices, the dense fibrous capsule which can build up around the implanted device can seriously impede its function, with consequences for the patient and costs to the health care system.
Trans-Atlantic team evades immune response with soft robotics
A trans-Atlantic partnership of scientists proposed what they called “a radical new vision” for medical devices to address the immune response problem. It included researchers from the Institute for Medical Engineering and Science (IMES) at the Massachusetts Institute of Technology; the National University of Ireland Galway (NUI Galway), and the Science Foundation Ireland (SFI) Research Centre for Advanced Materials and BioEngineering Research (AMBER), among others.
The team published a study describing the use of soft robotics to modify the human immune response to implanted devices in the journal Science Robotics.
The scientists created a tiny, mechanically actuated soft robotic device known as a dynamic soft reservoir (DSR) that has been shown to significantly reduce the build-up of the fibrous capsule by manipulating the environment at the interface between the device and the body. The device uses mechanical oscillation to modulate how cells respond around the implant. In a bio-inspired design, the DSR can change its shape at a microscope scale through an actuating membrane.
Diagram of implantable system showing a side-by-side implantation of a control and actuation group. Credit: Dolan et al., Science Robotics 4, eaax7043 (2019)
“This study demonstrates how mechanical perturbations of an implant can modulate the host foreign body response,” said Ellen Roche, the senior co-author of the study. “This has vast potential for a range of clinical applications and will hopefully lead to many future collaborative studies between our teams.”
Roche is an IMES core faculty member, assistant professor at the Department of Mechanical Engineering, and W.M. Keck Career Development Professor in Biomedical Engineering. She is also a former researcher at NUI Galway who won international acclaim in 2017 for her work in creating a soft robotic sleeve to help patients with heart failure.
“We feel the ideas described in this paper could transform future medical devices and how they interact with the body,” added Garry Duffy, professor in anatomy at NUI Galway, AMBER principal investigator, and a senior co-author of the study. “We are very excited to develop this technology further and to partner with people interested in the potential of soft robotics to better integrate devices for longer use and superior patient outcomes. It’s fantastic to build and continue the collaboration with the Dolan and Roche labs, and to develop a trans-Atlantic network of soft roboticists.”
“We are very excited to publish this study, as it describes an innovative approach to modulate the foreign-body response using soft robotics,” said Eimear Dolan, first author of the study, a lecturer of biomedical engineering at NUI Galway, and former researcher in the Roche and Duffy labs at MIT and NUI Galway. “I recently received a Science Foundation Ireland Royal Society University Research Fellowship to bring this technology forward with a focus on Type 1 diabetes. It is a privilege to work with such a talented multi-disciplinary team, and I look forward to continuing working together.”
The Robot Report is launching the Healthcare Robotics Engineering Forum, which will be on Dec. 9-10 in Santa Clara, Calif. The conference and expo will focus on improving the design, development and manufacture of next-generation healthcare robots. Learn more about the Healthcare Robotics Engineering Forum, and registration will be open soon.
As a patient who has had two pain pumps, three SCS and am with my 4th portacath, NOT ONE MD ever mentioned there was the possibility of an immune response, ever. In 1983 had a 12 Rush Rod to stabilize my left tibia after it a nasty spiral fracture. I learned after the fracture had healed, albeit 13 months later. My MD tells me the rod could delay healing or impede healing. Probably he says why my fx was deemed a non union fracture. I had to be plugged into an EBI machine that stimulates bone cell growth. I was plugged into that EBI unit 14 hrs a day. He told me it was used on race horses with shin splints. Oh joy, now I am treated as if I was a horse. What’s next?