Figure 4
The incidence and severity of vascular microhemorrhages increased following mannan-Aβ 28 immunizations. A. Quantification of Prussian blue staining based on the total number of positive profiles per section for mice injected with mannan-Aβ28, mannan-BSA, or non-immunized group. The levels of microhemorrhages were increased in vaccinated Tg2576 mice (n = 8) to 6.81 ± 2.6 compared to that of 2.31 ± 0.84 in mice immunized with mannan-BSA (n = 6), and 2.07 ± 0.58 in non-immunized animals (n = 5). *** Indicates P < 0.001. B-G. Examples of microhemorrhage severity in the brain sections of mice injected with mannan-Aβ28 (B, C, D), mannan-BSA (E, F), or non-immunized animals (G). B. A focal microhemorrhage (arrow) at the cortical-subcortical junction, below the gray-white matter border, lateral to hippocampus. C. Representative images of the Prussian blue-positive blood vessels (arrows) most prominent in the meningeal, superficial parenchymal and cortical vessels. D. A focal hemorrhage in the area of anterior commissure. E. A single microhemorrhage (arrow) in the white matter region. F. Microhemorrhage-free cortical and leptomeningeal areas. G. Two microhemorrhages (arrows) in the cortical and white matter regions. Original magnification, 10×, scale bar = 100 μm.