Neutrophil migration across HUVECs in response to S100A9.

<p>A) Increasing concentrations of S100A9 were added in the upper wells with neutrophils. IL-8 (5 ng/ml) or buffer was added to the lower wells and neutrophils were allowed to migrate for 2 h at 37°C. Data are the mean ± SEM of 3 experiments using neutrophils from different donors. *p<0.05, **p<0.01, one-way ANOVA, Dunnett’s multiple comparison test. B) S100A9 prolongs the time for neutrophil migration across endothelial cells. S100A9 (40 µg/ml) was added to the upper well with neutrophils. IL-8 (5 ng/ml) or buffer was added to the lower well and every 30 min for up to 2 h the upper wells were moved to new lower wells. The number of transmigrated cells was determined as described in Materials and Methods. Data shown represent the mean ± SEM of at least 3 experiments using neutrophils from different donors.