Fig. 2

Immunohistochemistry reveals increased tau hyperphosphorylation in TREM2 deficient hTau mice. a Immunohistochemistry was performed on 6-month hTau (Trem2 ^+/+) and hTau;Trem2 ^−/− mice using antibodies against AT8 and AT180 tau phospho-epitopes and revealed dramatically increased AT8 and AT180 staining in the cortex. b Quantitation of total p-Tau⁺ neurons revealed highly significant increases in total AT8⁺ and AT180⁺. c, d Laminar specific p-tau⁺ counts reveal significant increases in specific layers II-III in AT8⁺ and AT180⁺ neurons in hTau;Trem2 ^−/− mice. Additionally, robust increases in layers IV-VI were detected in hTau;Trem2 ^−/− mice. e Immunofluorescent co-labeling was performed with AT8 and macrophage/microglia specific Iba1 revealing reactive microglia in direct association with neurons heavily laden with phosphorylated tau in hTau;Trem2 ^−/− mice compared to hTau controls. All experiments used n = 4–6 (equal males and females) mice per group unless otherwise noted. At least two independent experiments were performed for each analysis. Bars, a-30 μm, e-100 μm