Expression of E-selectin and ICAM-1 is not sufficient to allow IgG-enhanced leukocyte adhesion to ECs. (A) HL60 cells were preincubated with pertussis toxin (500 μg/mL for 5 hours) before perfusion at 1.5 dynes/cm2 over TNFα-stimulated ECs coated with mAb RMAC8. (B) Flow cytometry profiles of E-selectin (mAb 1.2B6, dashed line), ICAM-1 (mAb 6.5B5, black line), and antibody control (mAb MOPC21, filled line) on HMEC-1 cells coinfected with adE-selectin (100 MOI) and adICAM-1 (50 MOI). Note increased expression of E-selectin and ICAM-1 compared with Figure 2A. (C) Lack of effect is shown of mAb RMAC8 on PMN interactions at 1.5 dynes/cm2 on resting ECs, despite increasing E-selectin and ICAM-1 expression by coinfection with adE-selectin (100 MOI) and adICAM-1 (50 MOI). Values are mean + SEM of 3 experiments (*P < .01, NS = not significantly different).
