Fig. 1.

IRF8 is required for ATP / ADP-induced microglial chemotaxis. Chemotactic responses of a wild-type (Irf8 ^+/+) and b IRF8-deficient (Irf8 ^−/−) microglia to ATP (0, 15, and 30 min) in the well chamber, using the EZ-TAXIScan system. Mean velocity (c), travel distance (d), and directionality (e) of Irf8 ^+/+, IRF8-heterozygous knockout (Irf8 ^+/−), and Irf8 ^−/−microglial cells during the 30-min test period after ATP injection (n = 83–237). Mean velocity (f), travel distance (g), and directionality (h) of Irf8 ^+/+and Irf8 ^−/−microglial cells during the 30-min test period after ADP injection (n = 120–138). *P < 0.05; ***P < 0.001