Inflammation affects stem cell function in old brains

In mammals, neurogenic regions of the brain contain stem cells that are able to produce new neurons in response to activation. This ability decreases with age but it is unclear why that is the case. Anne Brunet and colleagues use single-cell RNA-sequencing of young and old neurogenic niches in mice and uncover an increase in T cells in old niches. These T cells differ from those present in the blood and express interferon ligands, which correlates with an increase in the inflammatory signalling responses in old neural stem cells. These findings open possible future routes to prevent age-associated defects in brain.