Mef2C restrains microglial inflammatory response and is lost in brain ageing in an IFN-I-dependent manner

Microglia cells in the brain regulate immune responses, but in ageing can negatively affect brain function. Here the authors show that the chronic presence of type I interferon in aged mouse brain impedes cognitive ability by altering microglia transcriptome and limiting Mef2C, a microglia ‘off’ signal.