IL1R1 and Anxiety: In fact, psychosocial stress induces microglia‐dependent recruitment of circulating IL‐1β‐producing monocytes in mice stimulating the expression of brain endothelial interleukin‐1 receptor type 1 (IL‐1R1) and promoting anxiety‐like behaviours (McKim, Weber, et al., 2018; McKim, Yin, et al., 2018).