Expression and regulation of vascular cell adhesion molecule-1 in human umbilical vein endothelial cells induced by sera from severely burned patients

Objective: The purpose of this study was to determine the expression and regulation of vascular cell adhesion molecule (VCAM)-1 in human umbilical vein endothelial cells (HUVECs) induced by sera from severely burned patients. Design: Controlled laboratory study. Settings: Research laboratory in a university hospital. Subjects: HUVECs. Interventions: HUVECs were incubated with serum from eight healthy controls and eight patients with thermal injuries of >50% total body surface area. The experiment was repeated after pretreatment with pyrrolidine dithiocarbamate, an inhibitory effect on nuclear factor-kappaB activation, SB203580, a specific p38 mitogen-activated protein kinase inhibitor, and P098059, a mitogen-activated protein/extracellular signal-regulated kinase inhibitor. Measurements and Main Results: Protein and messenger RNA expression of VCAM-1 was measured by flow cytometry and reverse transcription-polymerase chain reaction respectively. Soluble VCAM-1 level in HUVECs culture supernatants was measured by enzyme-linked immunosorbent assay. Sera from severely burned patients showed a stimulatory effect on VCAM-1 messenger RNA levels and an increased VCAM-1 expression on the endothelial cell surfaces. The soluble form of VCAM-1 molecules was also elevated by the stimulation of burn sera. In vitro peripheral blood mononuclear leukocytes adherence to HUVECs incubated with burn sera was significantly increased compared with those incubated with control sera. Finally, these events were significantly inhibited by pretreatment with antioxidants pyrrolidine dithiocarbamate or SB203580, whereas PD98059 had no significant effect. Conclusions: These findings suggest that sera from severely burned patients induced up-regulation of VCAM-1 expressions in HUVECs, and this process might be largely dependent on oxidant-mediated nuclear factor-kappaB activation and p38 mitogen-activated protein kinase pathways.