Human BodyBrain
Immune cells prune your brain. They eat synapses whole.
The pruning is done by microglia, the brain's resident immune cells, which physically engulf and digest synapses during development. Connections get marked for removal by complement proteins — the same chemical labels the immune system normally sticks on germs.
Step by step
- Microglia are the brain's live-in immune cells, evolved to devour germs and debris.
- During development they also engulf living synapses, clearing the brain's weakest links.
- Complement proteins — labels meant for germs — mark which connections get eaten.
Source
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But when fuel runs low, cells take recycling a step further…
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