Chemokine gradients sequestered by endothelial HS effectively directs crawling leukocytes toward transmigration sites closer to the infection. (A) Displacement of crawling neutrophils (n = 48, 5 mice) from the adhesion point to transmigration site in hpa-tg cremaster muscle activated by an MIP-2-containing gel, placed extravascularly 400 μm from the observed venule (corresponding to 90 degrees in the polar chart). Representative confocal z-projections of (B) WT and (C) hpa-tg cremaster muscle activated with a FITC-MIP-2 (green) loaded gel. Endothelial cell junctions were stained with anti-CD31 mAb (red) and neutrophils with anti–Gr-1 mAb (blue) administered close intra-arterially.