Fig. 2

Ablation of Siglec-E exacerbates microglial activation in the brain. A C57BL/6 wild type and Siglec-E knockout mice were systemically treated by LPS (0, 3, or 5 mg/kg, i.p.), and 24 h later the mRNA expression of Siglec-E in the hippocampus was measured by qPCR (n = 5–8, *p = 0.01, Kruskal–Wallis test with post hoc Dunn’s multiple comparisons). Data are visualized using box plot. B Reverse transcription PCR was performed to examine the Siglec-E mRNA expression in the hippocampal tissues of wild type and Siglec-E knockout mice treated by LPS, with GAPDH as control. C Immunostaining for Siglec-E (green fluorescence) and Iba1 (red fluorescence) indicating the hippocampal microglial activation in wild type and Siglec-E knockout mice was performed 24 h after LPS treatment (5 mg/kg, i.p.). Representative images are presented here to exemplify the induction of Siglec-E and Iba1 as well as their colocalization in activated microglia. Scale bar: 50 μm. D Iba1-positive (Iba1⁺) microglia in the hippocampus were counted (Left) and their Iba1 expression levels were quantified by measuring the fluorescence intensity (Right) (n = 4–6, *p < 0.05, **p < 0.01, Mann–Whitney U test). Data are shown as mean ± SEM