Role of class-I PI3Ks in E-selectin expression in vitro. (A) E-selectin and PECAM-1 surface expression on HUVECs (± 5 μM TNFα) pretreated (1 hour) with the p110δ-specific inhibitor IC87114 (2 μM), the pan–class-I PI3K inhibitor LY294002 (10 μM), or the NF-κB function blocker Bay 11-7082 (10 μM). Adhesion molecule expression on nonstimulated cells is shown for comparison (top panels). Black lines represent vehicle control or cells treated with the indicated inhibitors (gray). (B) E-selectin expression on TNFα-stimulated HUVECs remains unchanged even at doses of IC87114 known to inhibit p110γ (50 μM). (C) TNFα-mediated NF-κB translocation in nuclear extracts from HUVECs pretreated with vehicle control or IC87114 as quantified by ELISA for the p50 subunit. Data represent the mean plus or minus SD for 1 of 3 experiments with similar results. *P < .01 as compared with cells treated with TNFα alone. (D) Percent reduction in attachment of purified human neutrophils to HUVEC monolayer that was pretreated with the indicated inhibitors prior to stimulation with TNFα (4 hours). Results are expressed as the percentage of cells that bound to the vehicle-treated substrate at a wall shear rate of 200 s^–1. Data represent the mean plus or minus SD for 3 experiments performed in duplicate. *P < .05 as compared with vehicle control.