Microglia In Neuroinflammation is an important cell type in the neurobiology of neurodegenerative diseases. This page provides detailed information about its structure, function, and role in disease processes.
Microglia are the resident immune cells of the central nervous system (CNS), constituting approximately 10-15% of all brain cells. As the primary innate immune effectors in the brain, microglia play critical roles in brain development, homeostasis, immune surveillance, and the inflammatory responses that characterize neurodegenerative diseases. [1]
| Property | Value | [2]
|----------|-------| [3]
| Category | Glial cells | [4]
| Location | Throughout CNS (brain and spinal cord) | [5]
| Cell Type | Resident macrophages | [6]
| Origin | Yolk sac progenitors (embryonic day 7-8) | [7]
| Function | Immune surveillance, inflammation, synaptic pruning |
| Taxonomy | ID | Name / Label |
|---|---|---|
| Cell Ontology (CL) | CL:0000129 | microglial cell |
| Database | ID | Name | Confidence |
|---|---|---|---|
| Cell Ontology | CL:0000129 | microglial cell | Medium |
| Cell Ontology | CL:4042028 | immature neuron | Medium |
Microglia originate from embryonic yolk sac progenitors that migrate into the developing brain during early embryogenesis (around embryonic day 7-8 in mice). Unlike other immune cells that turn over from bone marrow precursors, microglia are largely self-renewing under normal conditions, maintained through local proliferation.
The development and survival of microglia depend on several key signaling pathways:
Microglia exhibit remarkable morphological plasticity that correlates with their functional state:
Microglia maintain constant surveillance of the brain environment, monitoring for:
As professional phagocytes, microglia clear:
During development, microglia eliminate excess synapses through complement-mediated phagocytosis, refining neural circuits. This process continues in the adult brain at lower levels, contributing to synaptic plasticity.
Activated microglia release pro-inflammatory mediators:
Microglia can adopt multiple activation states, broadly categorized as:
Microglia play complex, dual roles in Alzheimer's disease:
Protective Functions:
Detrimental Effects:
Genetic Risk Factors:
Microglia contribute to dopaminergic neuron degeneration:
Common microglial markers used in research:
](/cell-types/glial-cells---overview-of-all-glial-cell-types
--astrocytes-in-brain-homeostasis---another-key-glial-cell
--neuroinflammation---inflammatory-mechanisms-in-neurodegeneration
--trem2---key-microglial-receptor-in-ad
--alzheimer's-disease---primary-neurodegenerative-disease
--parkinson's-disease---dopaminergic-neuron-degeneration
--blood-brain-barrier---cns-immune-privilege)## External Links
The study of Microglia In Neuroinflammation has evolved significantly over the past decades. Research in this area has revealed important insights into the underlying mechanisms of neurodegeneration and continues to drive therapeutic development.
Historical context and key discoveries in this field have shaped our current understanding and will continue to guide future research directions.
Heneka et al. [Neuroinflammation in Alzheimer's disease (2015)](https://doi.org/10.1016/S1474-4422(15). 2015. ↩︎
Salter & Stevens, Microglia emerge as central players (2017). 2017. ↩︎
Wolf et al. Microglia: biology and functions (2017). 2017. ↩︎
Hansen et al. TREM2 and microglial neurodegeneration (2018). 2018. ↩︎
Sarlus & Heneka, Microglia in Alzheimer's disease (2017). 2017. ↩︎
Liddelow et al. Neurotoxic reactive astrocytes (2017). 2017. ↩︎