Skip to main content
Fig. 7 | Journal of Neuroinflammation

Fig. 7

From: High-salt diet downregulates TREM2 expression and blunts efferocytosis of macrophages after acute ischemic stroke

Fig. 7

Enhancement of TREM2 signaling restores the efferocytic capacity and cellular inflammation resolution of macrophages in a high salinity environment. Bone marrow-derived primary cultured macrophages were infected with lentiviral vectors carrying TREM2-GFP cDNA (TREM2-Lenti) or control lentivirus carrying GFP only (NC-Lenti). Macrophages were subjected to analysis at 2 days after infection. a, b Transfected macrophages were treated in vitro with HS or PBS overnight and then subjected to efferocytic analysis with PI+ dead/dying neurons. The efferocytic efficiency of macrophages was evaluated with immunostaining (a) and flow cytometry (b). Engulfed dead/dying neurons (PI+Phalloidin+) per macrophage or the proportion of phagocytic macrophages (PI+F4/80+) was calculated at the corresponding time points. Data were collected from three independent experiments. *P < 0.05 and ***P < 0.001 versus NC-Lenti PBS group in one-way ANOVA. c In vitro protein expression of Arg1 and CD206 in transfected macrophages with HS or PBS treatment overnight was analyzed with flow cytometry. *P < 0.05 versus NC-Lenti PBS group in one-way ANOVA. d, e C57BL/6 mice with HSD or ND were first injected with clodronate liposomes to deplete monocytes/macrophages. Mice were then subjected to 60 min of tMCAO. Immediately after reperfusion, a single dose of 2x106 TREM2-overexpressing macrophages or NC macrophages were intravenously transferred in vivo. d The in vivo infarct volume of male mice was quantified on NeuN (red)-stained coronal sections at 3 days. Dashed lines outline the infarct area. N = 6 mice per group, *P < 0.05, **P < 0.01, and ****P < 0.0001, one-way ANOVA. e Confocal microscopy analysis of NeuN (blue) and Iba1 (red) double-staining in HSD mice. Quantification of the total number of Iba1+NeuN+ cells (microglia/macrophages that have engulfed neurons) and phagocytic index (the proportion of neurons engulfed by microglia/macrophages) in ischemic areas of HSD mice. N = 4 mice per group. *P < 0.05 and **P < 0.01 versus NC macrophage group in t test. f In vivo CD206 (red) expression in Iba1+GFP+ cells was analyzed via immunostaining. N = 4 mice per group. *P < 0.05 versus NC macrophage group in t test

Back to article page