Neuroimmunology: Mechanisms of Brain–Immune Communication in Health and Neurological Disease

This chapter reviews the cellular and molecular mechanisms governing bidirectional communication between the central nervous system and the peripheral immune system, including the roles of microglia, astrocytes, and brain-infiltrating immune cells in neuroinflammation and neuroprotection. It discusses recent advances in understanding the immunopathogenesis of neurological conditions with a clear immune component — including multiple sclerosis, neuromyelitis optica, autoimmune encephalitides, and neurological sequelae of systemic inflammatory diseases — with emphasis on how insights into neuroimmune crosstalk are generating novel therapeutic targets. The chapter also explores emerging evidence connecting peripheral immune status, the gut-brain axis, and neurodegeneration in conditions such as Alzheimer’s and Parkinson’s disease.