Females respond earlier and more strongly to aducanumab, and display greater immune deactivation at washout. (A and D) Volcano plots showing DEGs from bulk RNAseq of bulk hemiforebrain tissue in (A) females after two doses of 40 mg/kg aducanumab (Adu) or IgG control (week 3), (B) females after four doses (week 5), (C) males after four doses (week 5), (D) females after 30-wk washout period following four doses (week 34). Gene names displayed are the top 15 upregulated and downregulated genes. (E–F) Heatmap of selected canonical microglial activation genes curated by Chen and Colonna (2021) from multiple studies of microglial activation, showing differential expression of these genes after two doses of aducanumab (week 3 aducanumab versus week 3 IgG), four doses of aducanumab (week 5 aducanumab versus week 5 IgG), 15-wk washout (week 19 aducanumab versus week 19 IgG), and 30-wk washout (week 34 aducanumab versus week 34 IgG) in (E) males and (F) females. N = 3–4 mice/sex/treatment/time point, significance at adjusted P val < 0.1 with FDR correction (statistics computed automatically with analysis in edgeR; see Materials and methods for additional details). For heatmaps, *P_val_adj < 0.1, **P_val_adj < 0.05; ***P_val_adj < 0.01.