A transcriptomically distinct central nervous system macrophage found in the parenchyma of the central nervous system. Marker include CD11b-positive, F4/80-positive, and CD68-positive.
This extended description was generated by ChatGPT and reviewed by the CellGuide team, who added references, and by the CL editors, who approved it for inclusion in CL. It may contain information that applies only to some subtypes and species, and so should not be considered definitional. Microglial cells, sometimes referred to as microglia, are a type of glial cell that primarily exist within the central nervous system (CNS), notably in the brain and the spinal cord. Classified among the resident immune cells, microglial cells represent about 10% of all cells found within the CNS. These cells are derived from progenitor cells in the yolk sac, which differentiates them from other types of glial cells (such as astrocytes and oligodendrocytes) that are derived from neuroectodermal cell lineages. The primary role of microglial cells is to act as the first and main active form of immune defense in the CNS. They express a vast repertoire of pattern recognition receptors, which allow them to sense and eliminate microbes invading the CNS parenchyma. They represent one of the macrophage populations of the CNS and are responsible for phagocytosis (engulfing and destroying cellular waste or pathogens) in the neural environment. Microglial cells are particularly responsive to pathogens and injuries and change their morphology in reaction to inflammation or insult: In the normal state they are characterized by a ramified shape with small processes; in response to stimuli, some microglia mature and change to an amoeboid shape. Beyond their macrophagic activity, they also perform synaptic pruning during brain development, eliminate unnecessarily produced neurons, and facilitate tissue regeneration and repair. they play integral roles in regulating neural development and supporting cell survival and are important for maintaining tissue homeostasis. While their protective role generally benefits the brain, their over-activation can occasionally lead to neuro-inflammatory diseases, underlining the importance of balanced microglial cell functions. They have been extensively studied for their association with neurodegenerative diseases, such as Alzheimer's disease, Parkinson's disease, and multiple sclerosis.
Unlike macroglial cells, microglial cells arise from hematopoietic stem cells in the yolk sac during early embryogenesis that populate the central nervous system. They derive from embryonic mesoderm and are not from neuroectoderm where glioblast develops from. Markers: Mouse: CD11b+, F4/80+, CD68+. They represent ~12% of the cells in the CNS, but they are not uniformly distributed within the CNS. A normal adult mouse brain has approximately 3.5x10e6 microglia. Microglia are also reportedly CD3-negative, CD4-positive, CD8-negative, CD11b-positive, CD11c-high, CD14-negative, CD19-negative, CD45-low, CD56-negative, CD163-negative, CD200R-positive, CD281-positive, CD282-positive, CD283-positive, CD284-positive, CD285-positive, CD286-positive, CD287-positive, CD288-positive, CD289-positive, Gr1-negative, nestin-positive, and PU.1-positive.
class Information
class Relations
- glial cell
- central nervous system macrophage
- has plasma membrane partrosomeintegrin alpha-Mpr
- has plasma membrane partrosomeadhesion G protein-coupled receptor E1pr
- has plasma membrane partrosomemacrosialinpr
- develops fromrosomemesodermal cell
- develops fromrosome(stem cellandpart ofrosomeyolk sacuberon)
- capable ofrosomeinnate immune responsego