Figure 1: Detection of plasminogen bound to the surface of NB4 cells. Cells (5 × 105) were washed with PBS containing 1% BSA and 0.1% sodium azide (PBA) and incubated with 10 μM plasminogen (black tracing) or buffer (blue tracing) for 1 hour at 37°C, washed again and incubated with PBA containing 10% heat-inactivated normal rabbit serum for 10 minutes a room temperature. As an additional control, NB4 cells were treated with carboxypeptidase B (200 U/mL) before adding plasminogen (teal tracing). After incubation, supernatants were removed by centrifugation, incubated with mAb49 (130 nM) for 30 minutes a 4°C, washed and then stained with FITC-goat anti-mouse IgG, which was detected by FACS analyses. This research was originally published in [28].