Fig. 1
From: Evidence suggesting that microglia make amyloid from neuronally expressed APP: a hypothesis
-Alzheimer amyloid fibrils (A) being extruded from microglial coated pits (CP). Image reproduced with permission from Ref 5. (B) (i) Aβ formed by APP metabolism intramembraneously largely at neuronal synapses. (ii): the Aβ loaded membrane fragments are picked up in apoe lipoproteins: these attract microglia, via their TREM2 receptors, which are then activated. (iii) fragments are taken up by phagocytosis and engulfed and then these lipoproteins are delipidated, and begin to seed larger aggregates. Finally, these enter the efferocytosis pathway (iv) and extrude amyloid fibrils