Iloprost inhibits ICU COVID-19 IgG-induced increased thrombus formation. (A) PRP from healthy individuals with the blood group O was incubated with HC or ICU COVID-19 IgG in the presence of vehicle or Iloprost (20 nM). After reconstitution into autologous whole blood, samples were perfused through microfluidic channels at a shear rate of 1500^-1 (60 dyne) for 5 minutes. Pictures were acquired at x20 magnification in fluorescent (upper panel) as well as in the BF channel (lower panel). Scale bar 50 µm. (B) Mean percent of SAC by thrombus ± SEM induced by HC or ICU COVID-19 IgG in the presence of vehicle or Iloprost (20 nM). The number of patients and healthy donors tested is reported in each graph. See Figure 1 for P values and abbreviation definitions.