Neurons as cytokine sensors in the central nervous system.

Cytokines are key messenger molecules that bridge the nervous and immune systems through a bidirectional signalling network. Beyond their roles in development and homeostasis, neuronal cytokine sensing allows the central nervous system (CNS) to detect early immune perturbations, such as those triggered by emerging infections. Because neurons are postmitotic cells, rapid antipathogen responses are essential to prevent cell loss and ensure host survival. However, when CNS inflammation persists, as in chronic neuroinflammatory conditions such as multiple sclerosis or in age-associated inflammageing, cytokine signalling can become maladaptive and drive disease pathology. This review examines recent findings and emerging tools for studying how CNS neurons sense and respond to cytokines in both health and disease.