Fig. 2

Osteopontin (OPN) expands the number of neuroblasts in the healthy brain. Before (baseline) and at various time points after treatment, the total flux of photons was measured via bioluminescence imaging (BLI) as a surrogate for the number of doublecortin-positive (DCX⁺) neuroblasts. a Quantification of total flux was performed for each hemisphere and time point, as demonstrated on representative images, and a ratio was calculated between the hemispheres (the red rectangles in the baseline scan demonstrate measured ROIs of ipsi- and contralateral hemisphere). b Two days (D2) after i.c.v. injection of OPN, the ratio between right (injected) and left (contralateral) hemisphere regarding the total flux of photons was significantly higher compared with phosphate-buffered saline (PBS)-injected control mice, suggesting an expansion of DCX⁺ neuroblasts (means ± SEM; **p < 0.01). c Representative immunohistochemical images of DCX⁺ cells (red) costained with a nuclear marker (Hoechst; blue) in the subventricular zone (SVZ) ipsilateral to the injection. The number of DCX⁺ cells was increased 28 days after OPN treatment (right panels) compared with control (left panels; scale bars = 200 μm). d Twenty-eight days after injection of OPN, the area covered by DCX⁺ neuroblasts was significantly increased. This effect was more pronounced in the SVZ ipsilateral to injection compared with the contralateral side (means ± SEM; **p < 0.01, ***p < 0.001). e Representative immunohistochemical images of DCX⁺ cells (red) costained with a nuclear marker (Hoechst; blue) in the SVZ ipsilateral to the injection. The number of DCX⁺ cells was increased 2 days after OPN treatment (right panel) compared with control (left panel; scale bars = 100 μm). f Representative immunohistochemical images costaining bromodeoxyuridine (BrdU; green; labeling proliferating cells) and DCX (red; labeling neuroblasts) in the SVZ ipsilateral to the injection. The number of costained proliferating neuroblasts (BrdU⁺/DCX⁺) was increased 2 days after OPN treatment (right panel) compared with control (left panel; scale bars = 100 μm)