Mast Cells in the Brain: Enduring Mysteries, Emerging Roles

Mast cells are heterogeneous, tissue-resident immune sentinels best known for their roles in allergy and peripheral inflammation. The discovery of mast cells within the meninges and brain parenchyma over a century ago raised enduring questions regarding their function in the central nervous system (CNS), their ontogeny, and distinction from peripheral counterparts. Brain mast cells are sparse and predominantly located in perivascular niches rather than forming dense aggregates, a feature that ha