cAMP elevation prevents ICU COVID-19 IgG-induced formation of procoagulant PLTs. Panels (A-B) show ICU COVID-19 IgG-induced changes of procoagulant PLT markers in vehicle or Forskolin (2.25 µM) preincubated wPLTs. (A-B) ICU COVID-19 IgG-induced changes of (A) Δψ and (B) formation of CD62p/PS-positive PLTs were analyzed in vehicle or Forskolin preincubated wPLTs by FC. Panels (C-D) show ICU COVID-19 IgG-induced PLT changes in the presence of vehicle or Iloprost (20 nM). FC detected changes of (C) Δψ and (D) formation of CD62p/PS-positive PLTs induced by ICU COVID-19 IgG in vehicle or Iloprost preincubated wPLTs, respectively. (A,C) Data are presented as mean percentage ± SEM of Δψ depolarized PLTs and (B,D) mean percentage ± SEM of PS and CD62p-APC-positive-labeled wPLTs. The number of patients and healthy donors tested is reported in each graph. See Figure 1 for P values and abbreviation definitions.