Figure 4

Inflammatory leukocyte infiltration. Neutrophils (black arrows) were present as early as 6 h post-injury lining vessel walls (B, H&E) with intraparenchymal invasion by 24 h and beyond (C, H&E) as compared to sham tissue (A, H&E). A dense array of large macrophage-like cells (white arrows) were prominent by 72 h, particularly along the immediate border of the PBBI lesion (D, H&E). By day 7 an intracranial cavity had formed surrounded by a dense cellular infiltrate (E, H&E) and large, highly ramified astrocytes (F, GFAP). Bar = 20 μm (A-D), 100 μm (E-F).