Platelet-Neutrophil complex formation is increased during the early stages of invasive infection and decreased during late stage infection.

At 0, 5, 12, and 18 hours post infection with S. pyogenes the mice were sacrificed and a blood sample was taken by cardiac puncture. Flow cytometry of citrated blood was used to determine formation of platelet-neutrophil complexes in vivo (A) or post addition of thrombin ex vivo (B). Upregulation of CD11b on neutrophils was also determined (C). The median of the fluorescence for CD11b was measured for each sample with and without prior stimulation with fMLF ex-vivo. Stimulation with fMLF for each sample was set to 100% and the values displayed are for unstimulated samples. Horizontal line represents mean, p-value calculated using a t-test with Welch’s correction for unequal variances.