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…