Brain-computer interfaces are getting more advanced thanks to new manufacturing methods, novel computer algorithms, and our improved understanding of the brain. One persistent problem remains in how the immune system responds to the implants over an extended period of time. It may take years, but the electrodes prompt the body to form glial scars at implant site, reducing their effectiveness in interfacing with the brain.
To address this issue, researchers at Tel Aviv University in Israel are coating electrodes with interleukin (IL)-1 receptor antagonist, an immune suppressing protein, to prevent the immune system from paying attention to the implant.
Some detail from the study abstract in Journal of Biomedical Materials Research:
IL-1 receptor antagonist-coated electrodes and noncoated electrodes were chronically implanted in rats. An additional group of rats was chronically implanted with IL-1 receptor antagonist- and laminin-coated electrodes (as passive protein). Examination of glial scaring 1ne and 4 weeks after implantation indicated a significant reduction in the amount of glial scar in the vicinity of the IL-1 receptor antagonist-coated electrode in comparison to both noncoated electrode and laminin-coated electrodes. The results strongly suggest that active immune suppressing protein reduces the level of immune reaction to chronic electrodes already after 1 week after implantation and generates less immune reaction then passive protein coating.
Abstract in Journal of Biomedical Materials Research: Bioactive anti-inflammatory coating for chronic neural electrodes