Fig. 2. EphB1/Fc promotes endothelial cell migration. Confluent HRMEC were serum depleted prior to mechanical `wounding' to create circular defects of 600-900 µm diameter. The medium was supplemented with vehicle (NA), phorbol myristate acetate (PMA, 20 ng/ml), control IgG1 or EphB1/Fc (0.5 µg/ml each). Fractions of the areas remaining in triplicate wounds were determined by analysis of serial digital images obtained at the times indicated. Migration rates are expressed as a percentage of `wounds' closed per hour.