In vivo LEU/EC interactions and microvascular permeability. (A) Representative image showing LEU interacting with endothelium. White arrows indicate fluorescently labeled LEU rolling on endothelium. (B) Representative image showing FITC-albumin leakage in the cerebral microcirculation. The microvascular permeability index is expressed as the ratio of mean fluorescence of three separate locations outside the vessel wall (perivenular intensity, IP) to mean fluorescence of three separate locations within the venule (venular intensity, IV). (C) LEU rolling and FITC-albumin leakage in the pial penumbral microcirculation 48 hours after CCI. Compared with positive controls (CCI), both ODSH regimens reduced post-TBI LEU rolling and cerebrovascular albumin leakage. *p < 0.05, **p < 0.01 vs. CCI, #p < 0.05, ##p < 0.01 vs. 25ODSH.