Fig. 4

GPNMB/IBA-1-positive microglia cells cluster around individual plaque cores in 5XFAD brains. Triple immunofluorescence staining using antibodies against GPNMB (a), Aβ (b) and IBA1 (c) demonstrated the spatial co-localization of GPNMB-positive microglia cells around amyloid plaque cores in 12-month-old 5XFAD brains (d). Even though APP23 mice showed numerous activated microglia cells (g) clustered around amyloid plaques (f), no GPNMB signal could be detected (e,h). (i) RT-PCR analyses revealed significantly increased mRNA levels of CST7, TREM2, APOE, CLEC7A and CCL2 in 5XFAD brains when compared to WT and APP23 mice. However, levels of AIF1 and TMEM119 were comparable in all groups tested. All data are given as mean ± SD. ***P < 0.001; **P < 0.01. Scale bar: A-H = 33 μm