IL4-driven microglia modulate stress resilience through BDNF-dependent neurogenesis.

In light of the role of microglia in the pathogenesis of depressive disorders, we hypothesized that promoting a neuroprotective phenotype of microglia would improve stress responses and depressive behaviors. Consistent with this expectation, we found that in mice exposed to chronic mild stress (CMS), overexpression of hippocampal IL4 drove Arg1+ microglia to promote neurogenesis, which in turn attenuated depressive-like behaviors.