Fig 2: Chemotactic microglia migrate toward amyloid-beta plaques after interleukin-33 treatment.a-c, The induction of chemotactic microglia lasts throughout the chemotactic phase. a,b, Representative images (a) and quantification (b) showing the proportion of chemotactic microglia (that is, Vcam1+ Cx3cr1+ cells) after interleukin-33 (IL-33) treatment (3 h Con: n = 4; 3 h IL-33: n = 5; 8 h Con: n = 3; 8 h IL-33: n = 4; 24 h Con: n = 5; 24 h IL-33: n = 4; two-way ANOVA with Šidák’s multiple comparisons test). Arrowheads indicate Vcam1-expressing microglia. Scale bar = 10 µm. c, UMAP plots showing Vcam1 expression across conditions. d, Bar plot quantifying the proportions of chemotactic microglia (that is, Vcam1+ Cx3cr1+ cells) in uninjected and PBS-injected (Con) APP/PS1 mice (n = 4 mice per condition; two-tailed unpaired Student’s t-test). e, UMAP plots showing H2-Ab1 expression across conditions. f,g, Induction of MHC-II+ phagocytic microglia after IL-33 treatment. Representative contour plots (f) and quantification (g) showing the proportions of MHC-II+ phagocytic microglia (that is, MHC-II+ CD11b+ cells) after IL-33 treatment (Con: n = 3 mice; 3 h: n = 3 mice; 8 h: n = 3 mice; 24 h: n = 4 mice; one-way ANOVA with Dunnett’s multiple comparisons test). h,i, Chemotactic microglia gradually express MHC-II after IL-33 treatment. Representative contour plots (h) and quantification (i) showing the proportions of MHC-II–expressing chemotactic microglia (that is, MHC-II + VCAM1 + CD11b+ cells) after IL-33 treatment (3 h: n = 4 mice; 8 h: n = 4 mice; 24 h: n = 4 mice; one-way ANOVA with Dunnett’s multiple comparisons test). All data are mean ± s.e.m. Source data