Table 1.

Major immune effector cells in neurological disorders.

Cell	Central/Peripheral	Major functions	Associated neurological disorders	References
Microglia	Central	Cytokine secretion, phagocytosis	Most/all	(2, 6, 7)
Astrocytes	Central	BBB maintenance, cytokine secretion, glial scar formation	Most/all	(23, 24)
Mast cells	Both	Allergic reactions, inflammatory signaling, cytokine degradation, gut-brain axis regulation	Alzheimer’s, Parkinson’s	(25–27)
Ependymal cells	Central	BCSFB maintenance, pathogen surveillance, inflammatory signaling	Most/all	(28)
Neurons	Central	Inflammatory signaling via cytokines, DAMPs, and neurotransmitters/peptides	Most/all	(29–31)
Neutrophils	Peripheral	Cytokine/protease secretion, BBB breakdown, NET secretion	Most/all	(32, 33)
Basophils	Peripheral	Vasodilation via histamine secretion, anti-inflammatory signaling	Most/all	(32, 34)
Monocytes and monocyte-derived macrophages	Peripheral	Cytokine secretion, phagocytosis	Most/all	(35–37)
Natural killer cells	Both	Recognize and attack “non-self” cells, including cancer cells	Glioblastoma, multiple sclerosis	(38–40)
B cells	Peripheral	Immunological memory	Multiple sclerosis	(41)
CD4+ helper T cells	Peripheral	Inflammatory signaling, immunoregulation, neutrophil recruitment	Most/all	(42, 43)
CD8+ cytotoxic T cells	Peripheral	Destroy infected/damaged cells, including cancer cells	Glioblastoma, multiple sclerosis, neurodegenerative diseases	(44, 45)
T regulatory (Treg) cells	Peripheral	Immunomodulation, especially immunosuppression	Most/all	(46)
Gamma-delta (γδ) T cells	Peripheral	Recognize/attack damaged cells, including cancer cells, cytokine secretion	Glioblastoma, stroke, multiple sclerosis	(47)