Shown are cortical neurons and microglia derived from human induced pluripotent stem cells. Neurons are stained with microtubule associated protein (MAP2, gray), and microglia are stained with ionized calcium-binding adaptor molecule 1 (IBA1+, pseudo-colored in red). All cell nuclei are labeled with DAPI (blue). This co-culture platform revealed that these microglia can sense and dampen the repetitive action potential firing of cortical neurons carrying an epilepsy-associated voltage-gated sodium channel Nav1.2 (SCN2A) mutation. See the article by Zhefu Que, Maria Acosta-Olivero, et al. for more information on the role of microglia in regulating neural hyperactivity associated with an SCN2A mutation that causes epilepsy. Cover image: Zhefu Que.