Microglial signatures and their role in health and disease

Microglia are the primary innate immune cells in the CNS. In the healthy brain, they exhibit a unique molecular homeostatic ‘signature’, consisting of a specific transcriptional profile and surface protein expression pattern, which differs from that of tissue macrophages. In recent years, there have been a number of important advances in our understanding of the molecular signatures of homeostatic microglia and disease-associated microglia that have provided insight into how these cells are regulated in health and disease and how they contribute to the maintenance of the neural environment. Technological advances have allowed the molecular ‘signatures’ of microglia to be characterized, providing insight into their roles in CNS function. Weiner and Butovsky discuss the plasticity of these signatures in health and disease and consider the mechanisms underlying their establishment, maintenance and regulation.