Fig. 1

Simplified schematic view of meningeal lymphoid immune cells with established roles in cognition, behavior and CNS tolerance. In steady-state, immune cytokines secreted by meningeal immune cells can act upon brain cells and influence behavior and cognition. Some cytokines can directly exert their effect by binding on the receptors expressed by neurons (IL17, IFNγ and IL4). The precise mechanisms by which they cross the reach the parenchyma is still unknown. CNS antigens are drained from the subarachnoid space to the dura where they potentially interact with dural B cells. Black arrows indicate the origin and target of each cytokine and colored arrows resume the resulting functions. NK: natural killer; ILC1: innate lymphoid cell type 1; MAIT: mucosal-associated invariant T; Ach: acetylcholine; IFN: interferon; IL17: interleukin 17; IL4: interleukin 4; CNS: central nervous system; ROS: reactive oxygen species; CSF: cerebrospinal fluid; BDNF: brain-derived neurotrophic factor; DA: dopamine; VTA: ventral tegmental area