Leukocyte adhesion during inflammation in vivo. (A) Number of adherent leukocytes (mean ± SEM per mm² of surface area) in unstimulated mouse cremaster muscle venules of WT control and ST3Gal-IV^−/− mice. (B) Increase in the number of adherent leukocytes (mean ± SEM per mm² of surface area) 3 min after systemic injection of 600 ng CXCL1 or CXCL8 in WT control, ST3Gal-IV^−/−, WT control (plus 4 μg PTx), ST3Gal-IV^−/− (plus 4 μg PTx), and CXCR2^bm−/− mice. PTx was injected 3 h before cremaster muscle exteriorization. (C) Leukocyte adhesion (mean ± SEM) was observed in 3-h TNF-α–treated cremaster muscle venules of WT control, ST3Gal-IV^−/−, and CXCR2^bm−/− mice. Additionally, pretreatment of TNF-α–treated WT control, ST3Gal-IV^−/−, and CXCR2^bm−/− mice was conducted with 4 μg PTx and/or 100 μg E-selectin mAb 9A9 5 min before TNF-α injection. Data in A–C were obtained from at least three independent experiments per group. *, P < 0.05 versus WT control mice (A and C); *, P < 0.05 versus WT control mice treated with CXCL1 or CXCL8, respectively (B). Videos 1 and 2 are available.