Sepsis platelets show impaired (hem)ITAM signaling. Washed platelets (500 000/µL) of healthy controls (HC) and patients with sepsis (S) were stimulated with CRP-XL (C) and rhodocytin (R). Lysis was done at the following time points: C: 5 minutes; R: 10 minutes. I: admission day; II: day 5 to 7; and III: day of ICU discharge. (A-C) Western blot analysis of platelet lysates. Staining was performed with anti-phospho-tyrosine antibody 4G10. Band intensity (72 kDa) was set in relation to signal intensity of Syk or GAPDH in AU. Representative blots are shown in panels A (time point I) and B (time point III). (D-F) Phosphorylation of signaling peptides Syk and Lat was investigated by immunoblot. One representative blot is shown in panel D. (G-J) Phosphorylation analysis of immunoreceptor tyrosine inhibitory motif signaling associated phosphatases SHP-1 and SHP-2. Phosphoprotein intensity was set in relation to intensity of unphosphorylated protein shown in panels H and J. Representative western blots are shown in panels G and I. All graphs display median ± IQR.