A, monocyte transmigration across Adam15−/− aortic ECs was significantly attenuated (n=4; *p<0.05 vs. Adam15+/+ ECs). B, depletion of ADAM15 with siRNA (siADAM15) in HUVECs attenuated monocyte transmigration across the HUVEC monolayer. Scrambled siRNA (siScrm) and non-transfected (NT) were used as negative controls (n=4; *p<0.05 vs. siScrm).C and D, ADAM15 deficiency in ECs did not affect surface expression of main Ig superfamily of cellular adhesion molecules (CAM), including ICAM-1, Nectin-2, PECAM-1, and VCAM-1. C, quantitative analysis of CAM expression (n=4); D, representative flow cytometric histograms.