Anatomy:

• Small cells with highly branched, motile processes.

• Express Iba1 and CD11b.

• Constantly surveil the environment (ramified state); become amoeboid when activated.

Function:

• Act as resident immune cells of the CNS.

• Phagocytose apoptotic cells, debris, pathogens.

• Release cytokines, chemokines during inflammation.

• Prune synapses during development and plasticity via complement signaling.

• Can become neurotoxic when chronically activated (e.g., in neurodegeneration).