Adhesion of mPB CD34⁺ cells on HBMECs. Adhesion assays were run in the presence of 20 μg/mL of the different antibodies. The number of mAb-pretreated cells that had adhered was compared with nonpretreated cells (100% arbitrarily). An anti-CD106 mAb was used as a positive control of the inhibition of adhesion. Data are mean ± SEM of 3 experiments.