Immune cell regulation of glia during CNS injury and disease

Glial cells are abundant in the CNS and are essential for brain development and homeostasis. These cells also regulate tissue recovery after injury and their dysfunction is a possible contributing factor to neurodegenerative and psychiatric disease. Recent evidence suggests that microglia, which are also the brain’s major resident immune cells, provide disease-modifying regulation of the other major glial populations, namely astrocytes and oligodendrocytes. In addition, peripheral immune cells entering the CNS after injury and in disease may directly affect microglial, astrocyte and oligodendrocyte function, suggesting an integrated network of immune cell–glial cell communication. Interactions between immune cells and neurons are now widely believed to be important for the regulation of brain function. In their Review, Greenhalgh, David and Bennett highlight the importance of interactions between resident and infiltrating immune cells and the brain’s other major cellular population — glial cells — for brain function.