Figure 12

Coexpression of CD11b (red) and NeuN (blue) with CD68 (green) at 24 h (A-A'-B-B') and 7d (C-C'-D-D') or with Ym1 at 24 h (E-E'-F-F') and 7d (G-G'-H-H') after pMCAO. In the ischemic core CD11b/CD68 double positive cells envelop NeuN positive cells, possibly indicating phagocytosis of neurons (A; 3D rendering in A'). The same interaction was observed in the border zone (B-B'). At 7d after ischemia, when CD68 expression is enhanced (Figure 3) in both ischemic core and border zone, CD11b/CD68 double positive cells enwrap neurons, suggesting active phagocytosis also at this time point (C-C'-D-D'). At 24 h after pMCAO in the ischemic core, where Ym1 positive cells are exclusively located, CD11b/Ym1 double positive cells do not appear involved in a phagocytic interaction with neurons (NeuN positive cells, E; 3D rendering on E'). CD11b single positive cells in both ischemic core (E-E') and border zone (where Ym1 is not expressed, F-F') surround neurons. At 7d after ischemia part of CD11b/Ym1 double positive cells engage a phagocytic appearance by enveloping neurons in ischemic core (G-G') coherently with their partially CD68 positive phenotype at this time point (Figure 8). In the border zone at 7d (Ym1 is absent) CD11b single positive cells still enwrap neurons (H-H'). Data are representative of 3 independent experiments. Bar: 20 μm.