Figure 2: In vitro and in vivo ATRA modulation of plasminogen binding to NB4 cells and APL blast cells. (a) NB4 cells were incubated with 1 μM all-trans retinoic acid (ATRA) for 48 hours, washed and preincubated with plasminogen (10 μM) followed by FACS analyses with mAb49 (orange tracing). FACS analyses with mAb49 of untreated NB4 cells preincubated with either plasminogen (black tracing) or buffer (blue tracing) detected by antiplasminogen mAb49. (b) Plasminogen bound to blast cells from a patient with APL (CD33+; HLDR Negative) was monitorized in whole blood using mAb49. Analyses were performed at day 0 of ATRA treatment (red tracing) and after ATRA treatment for either 4 days (orange tracing) or 5 days (pink tracing). As a negative control FACS analysis with an isotype control antibody (turquoise tracing). (c) FACS analysis using mAb49 (red tracing) or isotype control (turquoise tracing) of blood from a patient with an M1 leukemia. This research was originally published in [28].