Leukocyte rolling flux and velocity in cremaster microcirculation of PSGL-1^-/- mice treated with TNF-α. Leukocyte rolling flux (A) and leukocyte rolling velocity (B) in cremaster microcirculation of PSGL-1^-/- mice treated 3 hours before with TNF-α applied locally (0.5 μg/mouse). The effect of anti–E-selectin antibody was tested. The first bar at left represents the values for leukocyte rolling and leukocyte rolling velocity under control conditions. Data are presented as mean ± SEM. ^*P < .05 relative to PSGL-1^-/- mice treated with TNF-α (second column).