Fig. 3

COVID-19 patients have higher levels of soluble JAM-C and of neutrophil reverse transendothelial transmigration. a Soluble JAM-C (sJAM-C) was quantified by ELISA; results are expressed as pg/ml. b, c Quantification of neutrophils undergoing reverse-endothelial transmigration (reverse transmigrated neutrophils, rTEM). Whole-blood samples were incubated for 45 min at 4 °C with FITC-anti-human CD181 (CXCR1) and PE-anti-human CD54 antibodies. b Representative dot plots of the neutrophil phenotype according to CXCR1 and CD54 expression in an HC (left) and a COVID-19 patient (right); c Percentage of rTEM neutrophils. Samples came from age-matched healthy controls (HCs) (n = 38), CAP patients (n = 22), and COVID-19 patients at day 1 (n = 53), day 3 (n = 49), and day 7 (n = 40). Values are means ± SEM. *P < 0.05, **P < 0.01, ***P < 0.001, adjusted for age