OBJECTIVETo investigate the influence of burn serum on the expression of vascular cell adhesion molecule-1 (VCAM-1) of human umbilical vein endothelial cells (HUVECs) andits signal transduction mechanism.

METHODSHUVECs cultured in vitro were employed for the experiment, and were divided into normal control (NC, with addition of normal serum), burn serum (BS, with addition of burn serum), SB203580 (with addition of 10 micromol/L SB203580 treatment 1 hour before burn serum treatment) and PDTC [with 10 mmol/L pyrrolidine dithiocarbamate (PDTC) 1 hour before burn serum treatment] groups. Protein and mRNA expression of VCAM-1 in HUVECs was measured by flow cytometry and reverse transcription polymerase chain reaction (RT-PCR) respectively at 0, 6, 12, 24 and 36 hours after burn serum treatment. The expression of VCAM-1 on HUVEC surface and the soluble VCAM-1 (sVCAM-1) content in HUVECs culture supernatants were measured by ELISA at 24 hours after the serum stimulation. Adherence of peripheral blood mononuclear leukocytes (PBMC) adherence to HUVECs was also observed in vitro.

RESULTSThe expression of VCAM-1 mRNA increased obviously in BS group after the burn serum stimulation and reached peak level at 24 post stimulation hour (PSH), and it decreased thereafter. The above expression was significantly decreased in SB203580 and PDTC groups at 24 PSH, but there was no difference compared with normal control (P > 0.05). The VCAM-1 expression on the membrane of HUVEC was evidently higher in BS group (66.5 +/- 6.2) than that in NC group (19.1 +/- 1.9, P < 0.05) at 24 PSH, but it was decreased significantly in SB203580 (21.7 +/- 2.3) and PDTC (23.1 +/- 2.4) groups and there was no significant difference compared with NC group (P > 0.05), and which was evidently lower than that in BS group (P < 0.05). The VCAM-1 content in the supernatant of BS group (125 +/- 10 ng/L) was obviously higher than that in NC (23 +/- 3 ng/L), SB203580 (27 +/- 5 ng/L) and PDTC (29 +/- 5 ng/L) groups. (P < 0.05). The number of PBMCs adherent to HUVECs in BS group [(197 +/- 11)%] was much larger than that in NC group [(100 +/- 4)%], SB203580 group [(113 +/- 7)%] or PDTC group [(97 +/- 112)%] at 24 PSH (P < 0.05), but no difference between NC group and SB203580, PDTC groups (P > 0.05).

CONCLUSIONBurn serum can enhance the expression of VCAM-1 in HUVECs through p38 MAPK signaling pathway, and the activation of NF-kappaB was also involved in this process.