Figure 4: Microglia-derived TNF-α alleviates aberrant neurogenesis.

(a) qRT-PCR analyses of Tnf-α levels in the DG of WT and TLR9 KO mice at the indicated time points after seizure. Experimental controls were KA-untreated WT and TLR9 KO mice, respectively (n=3 animals). *P<0.05 by analysis of variance (ANOVA) with Tukey post-hoc tests. (b) Experimental scheme for assessing aNS/PC proliferation in microglia culture-derived CM pretreated with TNF-α-neutralizing antibody or IgG control. (c) Representative images of EdU (red), active caspase3 (green) and Hoechst (blue) staining in aNS/PCs cultured with the indicated CM from microglia (n=4 experiments). Scale bar, 50 μm. (d) Quantification of EdU+ or active caspase3+ cells in c (n=4 experiments). (e) Experimental timeline for assessing aNS/PC proliferation in thalidomide (Thal)-treated mice. (f) Representative images of BrdU+DCX+ newly generated immature neurons in the DG (n=4 animals). Scale bar, 50 μm. (g,h) Quantification of the number of BrdU+DCX+ cells in f, in the DG (g) and in the hilus (h) (n=4 animals). *P<0.05 and **P<0.01 by ANOVA with Tukey post-hoc tests.