Figure 4

IgG extravasation and polymorphonuclear (PMN) leukocyte infiltration after acute stroke. The contralateral - ipsilateral difference in IgG staining was greater in wild-type than in sham surgery or P-selectin-deficient mice (A), indicating more severe BBB injury in mice expressing P-selectin (* p < 0.05 for wild-type vs. knockout (KO) mice). Also shown are representative sections stained for IgG immunohistochemistry from sham, wild type and P selectin KO mice (B). Numbers PMN leukocytes was greater in ischemic brains of wild-type animals compared to those in P-selectin deficient animals or shams (C) (* p < 0.05, vs sham). Representative intravital microscopy images of the pial vessels obtained either immediately or 30 minutes after intravenous administration of FITC-dextran (2000 kDa) in a wild-type mouse or a P-selectin knockout mouse at 24 hours after transient middle cerebral artery occlusion or a mouse subjected to sham surgery (D), FITC extravasation is evident in the wild-type mouse expressing P-selectin but not in the P-selectin KO animal.