Figure 2.

TREM2 deficiency leads to reduced microgliosis in response to KA treatment in mouse brain. Trem2^−/− or WT mice were intraperitoneally injected with 25 mg/kg KA at 8 weeks of age and mouse brains were dissected 3 d later. A, Coronal sections from Trem2^−/− or WT mouse brains were stained with Iba-1 (green) for microglia. Representative images are shown. B, D, Number of microglia double stained with DAPI (blue) and Iba1 (green) was quantified per HPF in Trem2^−/− or WT hippocampi and cortices. C, E, Microglia number response to KA was assessed by quantifying the cell number ratio of KA group to control group in WT or Trem2^−/− brains. F, G, Quantification of microglial cell body (area, in square micrometers) per HPF in the hippocampi and cortices of WT or Trem2^−/− brains with or without KA treatment. H, I, Quantification of microglial process per HPF in the hippocampi and cortices of WT or Trem2^−/− brains with or without KA treatment. Scale bar, 100 μm. Data are plotted as mean ± SEM (n = 5). *p < 0.05; **p < 0.01; ***p < 0.001; ns, not significant.