Fig. 3

APOE4 microglia extend their processes in response to ATP slower than APOE3 microglia. A Representative confocal time-lapse showing microglial response (green) to 3 mM ATP in a patch pipette (red) in acute entorhinal slices. Scale bar 20 µm. B Illustration of the microglial processes manual tracking over the course of 30 min. Scale bar 20 µm. C-D APOE3 (E3) and APOE4 (E4) microglia responding to patch pipette containing ATP (shown as dashed triangle) in the CA1 (C) and EC (D). E–F Processes velocity in the CA1 (C) and EC (D) in response to 1 mM, 3 mM, and 10 mM ATP. Bar graphs represent the mean velocity ± SEM. Individual points (circles, male; triangle, females) represent the average process velocity (3 processes per cell) of each microglia (3–5 cells per animal). 3–4 animals per genotype per sex (6 months old). Two-way ANOVA with Sidak’s multiple comparison post-hoc analyses *p < 0.05, ****p < 0.0001