Fig. 4

Neutrophil abnormalities are associated with vascular inflammation in COVID-19 patients. a–f Evaluation of soluble markers of endothelial activation. Levels of soluble P-selectin (a) and E-selectin (b) were quantified by ELISA; results are expressed as pg/ml. Correlation between soluble P-selectin and CD11b expression on neutrophils (c), circulating LTB4 levels (d), circulating JAM-C level (e) and the percentage of rTEM neutrophils (f). g–k Measurement of circulating levels of cytokines. Soluble VEGF was quantified by ELISA; results are as pg/mL (g). Correlation between soluble VEGF and VEGF-R1 (h). IL-6 (i), and IL-10 (j) were quantified by ELISA; results are as pg/ml. Correlation between soluble IL-10 and ROS production by fMLP-stimulated neutrophils (k). All samples came from age-matched healthy controls (HC, n = 40) and COVID-19 patients at day 1 (n = 53), day 3 (n = 49) and day 7 (n = 40). Values are means ± SEM. *Significantly different from controls P < 0.05, **P < 0.01, ***P < 0.001, adjusted for age