To determine whether factors in SCLS sera could evoke endothelial barrier dysregulation by inducing leukocyte adhesion, we incubated HUVECs with acute and baseline sera from SCLS subjects or healthy donors and analyzed surface expression of E-selectin, VCAM-1 and ICAM-1 by flow cytometry. Here, ICAM1 is linked to Systemic capillary leak syndrome.