Foreign Body Reaction to Implanted Biomaterials and Its Impact in Nerve Neuroprosthetics

The implantation of any foreign material into the body leads to development an inflammatory and fibrotic process—the reaction (FBR). Upon a tissue, cells immune system become attracted attempt degrade it. If this degradation fails, fibroblasts envelop form physical barrier isolate it from rest body. Long-term medical devices faces great challenge presented by FBR, as cellular response disrupts interface between implant its target tissue. This is particularly true for nerve neuroprosthetic implants—devices implanted nerves address conditions such sensory loss, muscle paralysis, chronic pain, epilepsy. Nerve neuroprosthetics rely on tight interfacing tissue electrodes detect tiny electrical signals carried axons, and/or electrically stimulate small subsets axons within nerve. Moreover, advances in microfabrication drive field increasingly miniaturized implants, need stable, intimate implant-tissue likely quickly limiting factor new technologies. Here, we provide overview material-cell interactions leading FBR. We review current technologies (cuff, penetrating, regenerative interfaces) how long-term function these limited Finally, discuss properties (such stiffness size), pharmacological therapies, or use biodegradable materials may be exploited minimize FBR implants improve their stability.