Molecules involved in the transmigration of DC across resting EC. A porous polycarbonate filter was coated with a monolayer of EC and placed in modified Boyden chamber. ⁵¹Cr-labeled DC were preincubated for 20 minutes at room temperature with the indicated MoAb and then seeded in the upper compartment and coincubated with EC for 1 hour at 37°C. Results are expressed as percent of adherent and transmigrated cells (see Materials and Methods), mean ± SEM of three replicates. **Statistically significant at P < .01 versus medium control.