[Role of microglia in neuronal circuit formation]

Microglia are known to maintain the cellular environment in the brain via their phagocytic activity. Further, recent studies have demonstrated that microglia play an important role in neuronal circuit formation. During neuronal development, new axonal and dendritic processes are formed, but excessive connections are eliminated appropriately; microglia participate in this pruning process. Moreover, evidence shows that microglia contribute to synaptic maturation by secreting various molecules.