Peripheral B cell populations tune spontaneous neuronal activity in the uninjured hippocampus after stroke

We uncover crucial insights on the capacity of circulating B cells to directly modulate hippocampal network activity, showing that B cells are not just passive players, but active neuromodulators whose effects are dependent on sex, age, and stroke injury status. In fact, B cells are central players to functional recovery whose evolving role shifts over time, from acutely beneficial and neurotrophic to chronically maladaptive, depending on timing, context, and responding B cell subset. Our study demonstrates a mechanistic link between systemic immune modulation and neuronal calcium activity. This integrative perspective aligns with Neuron's mission to publish studies that link cellular processes to systems-level functions. These novel findings also add to a more unified model of neuro-immune interactions that highlights how immunotherapies could be harnessed to improve neuronal function during stroke and aging, with several FDA-approved immunotherapeutics available to modulate systemic adaptive immune responses.