| Microglia in Synapse Pruning | |
|---|---|
| Lineage | Glia > Microglia > Synapse Pruning |
| Markers | C1Q, C3, CR3, CD68, IBA1 |
| Brain Regions | Brain Parenchyma, Cortex, Hippocampus |
| Disease Vulnerability | AD, Schizophrenia, ASD, MS |
Microglia-mediated synapse pruning is a critical developmental process whereby microglia eliminate redundant or inappropriate synaptic connections. This activity shapes neural circuit formation during development and, when dysregulated, contributes to neurodegenerative and psychiatric disorders[1][2].
Microglia in Synapse Pruning are a specialized population of brain immune cells classified within the Glia > Microglia > Synapse Pruning pathway. These cells are primarily found in Brain Parenchyma, cortex, and hippocampus, characterized by expression of marker genes including C1Q, C3, CR3, CD68, and IBA1. They are selectively vulnerable or involved in Alzheimer's disease, schizophrenia, autism spectrum disorder, and multiple sclerosis[3].
| 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 |
The complement system plays a central role in microglia-mediated synapse elimination:
| Protein | Function | Role in Pruning |
|---|---|---|
| C1Q | Complement component | Tags synapses for elimination |
| C3 | Opsonin | Marks synapses for phagocytosis |
| CR3 | Receptor | Mediates microglial recognition |
| CD68 | Phagocytic marker | Engulfment activity |
| TREM2 | Triggering receptor | Apoptotic cell clearance |
Microglia phagocytose synapses through:
Synapse pruning occurs during specific developmental windows:
Neural activity regulates pruning intensity:
In AD, synapse pruning becomes pathological:
Schizophrenia involves pruning abnormalities:
ASD shows altered pruning:
In MS:
| Agent | Target | Approach |
|---|---|---|
| ANX-005 | C1q | Block complement tagging |
| Avacopan | C5aR | Inhibit complement inflammation |
| NLY01 | GLP-1R | Modulate microglial phenotype |
Schafer DP, Stevens B. Microglia Function in Central Nervous System Development and Plasticity. Cold Spring Harbor Perspectives in Biology. 2015. 2015. ↩︎
Hong S, et al. Complement and microglia mediate synapse elimination during development. Science. 2016. 2016. ↩︎
Stevens B, et al. The classical complement cascade mediates CNS synapse elimination. Cell. 2007. 2007. ↩︎