Data from: Microglial motility is modulated by neuronal activity and correlates with dendritic spine plasticity in the hippocampus of awake mice

Microglia, the resident immune cells of the brain, play a complex role in
health and disease. They actively survey the brain parenchyma by
physically interacting with other cells and structurally shaping the
brain. Yet the mechanisms underlying microglial motility and significance
for synapse stability, especially in the hippocampus during adulthood,
remain widely unresolved. Here we investigated the effect of neuronal
activity on microglial motility and the implications for the formation and
survival of dendritic spines on hippocampal CA1 neurons in vivo. We used
repetitive two-photon in vivo imaging in the hippocampus of awake and
anesthetized mice to simultaneously study the motility of microglia and
their interaction with dendritic spines. We found that CA3 to CA1 input is
sufficient to modulate microglial process motility. Simultaneously, more
dendritic spines emerged in mice after awake compared to anesthetized
imaging. Interestingly, the rate of microglial contacts with individual
dendritic spines and dendrites was associated with the stability, removal,
and emergence of dendritic spines. These results suggest that microglia
might sense neuronal activity via neurotransmitter release and actively
participate in synaptic rewiring of the hippocampal neural network during
adulthood. Further, this study has profound relevance for hippocampal
learning and memory processes.