• Molecules and Cells
• /
• v.44 no.5
• /
• pp.281-291
• /
• 2021

Tissue-resident macrophages play an important role in maintaining tissue homeostasis and innate immune defense against invading microbial pathogens. Brain-resident macrophages can be classified into microglia in the brain parenchyma and non-parenchymal brain macrophages, also known as central nervous system-associated or border-associated macrophages, in the brain-circulation interface. Microglia and non-parenchymal brain macrophages, including meningeal, perivascular, and choroid plexus macrophages, are mostly produced during embryonic development, and maintained their population by self-renewal. Microglia have gained much attention for their dual roles in the maintenance of brain homeostasis and the induction of neuroinflammation. In particular, diverse phenotypes of microglia have been increasingly identified under pathological conditions. Single-cell phenotypic analysis revealed that microglia are highly heterogenous and plastic, thus it is difficult to define the status of microglia as M1/M2 or resting/activated state due to complex nature of microglia. Meanwhile, physiological function of non-parenchymal brain macrophages remain to be fully demonstrated. In this review, we have summarized the origin and signatures of brain-resident macrophages and discussed the unique features of microglia, particularly, their phenotypic polarization, diversity of subtypes, and inflammasome responses related to neurodegenerative diseases.

• Korean Journal of Veterinary Research
• /
• v.45 no.1
• /
• pp.7-15
• /
• 2005

To elucidate the roles of phospho-IkB expression in the development and progression of EAE, we investigated the expression of phospho-IkB in the central nervous system (CNS) of rats during experimental autoimmune encephalomyelitis (EAE) using immunohistochemistry and Western blot analysis. In Western blot analysis, the increased expression of phospho-IkB went parallel to severity of EAE. The expression of phospho-IkB increased significantly at the peak stage of EAE followed by gradual decrease. Immunohistochemical studies showed that the phospho-IkB immunoreactivity was mainly expressed in inflammatory cells (macrophages, T cells) and glial cells (astrocytes, microglial cells) at the peak stage of EAE and disappeared at the recovery stage. These findings suggest that the phosphorylation of IkB is closely associated with autoimmune inflammation in the CNS and plays an important role in the initiation and progression of EAE.