Researchers from the University of Cambridge developed a new type of neural implant that could restore limb function to those with amputations and others who have lost the use of their arms or legs.
In a study carried out in rats, researchers used the biohybrid device to improve the connection between the brain and paralyzed limbs. The device combines flexible electronics and human stem cells to better integrate with the nerve and drive limb function.
Previous attempts at using neural implants to restore limb function have mostly failed, as scar tissue tends to form around the electrodes over time, impeding the connection between the device and the nerve. By sandwiching a layer of muscle cells reprogrammed from stem cells between the electrodes and the living tissue, the researchers found that the device integrated with the host’s body, and the formation of scar tissue was prevented. The cells lived on the electrode for the duration of the 28-day experiment, the first time that cells have been shown to survive an extended experiment of this kind.
According to the researchers, by combining two advanced therapies for nerve regeneration—cell therapy and bioelectronics—into a single device, they can overcome the shortcomings of both approaches, improving functionality and sensitivity.
The biohybrid device was implanted into the paralyzed forearm of the rats. The stem cells, which had been transformed into muscle cells prior to implantation, integrated with the nerves in the rat’s forearm. While the rats did not have movement restored to their forearms, the device was able to pick up the signals from the brain that control movement. If connected to the rest of the nerve or a prosthetic limb, the device could help restore movement. The cell layer also improved the function of the device by improving resolution and allowing long-term monitoring inside a living organism.
The researchers say that their approach has multiple advantages over other attempts to restore function in people with amputations. In addition to its easier integration and long-term stability, the device is small enough that its implantation would only require keyhole surgery.
“This interface could revolutionize the way we interact with technology,” said co-first author Amy Rochford, a doctoral student in the university’s department of engineering. “By combining living human cells with bioelectronic materials, we’ve created a system that can communicate with the brain in a more natural and intuitive way, opening up new possibilities for prosthetics, brain-machine interfaces, and even enhancing cognitive abilities.”
The open-access study, “Functional neurological restoration of amputated peripheral nerve using biohybrid regenerative bioelectronics,” was published in Science Advances.
Editor’s note: This story was adapted from materials provided by the University of Cambridge.