Influence of complement bypass-activation on IL-8 expression in endothelial cells

AIM:To study the induction of IL-8 expression by bypass-activated complement in human umbilical vein endothelial cells (HUVECs) and regulatory effect of nuclear factor-kappa B on the expression of IL-8. METHODS:In vitro, zymosan-activated human serum(ZAHS) directly challenged the HUVECs monolayers. Following techniques were used in the experiment: ① RIA for measurement of IL-8,ISH for measurement of their mRNA.② EMSA for measurement of nuclear factor-kappa B(NF-κB). RESULTS:①After HUVECs monolayers were stimulated with ZAHS, the level of IL-8 increased significantly at 4 h. ②The NF-κB activity began upregulated within 30 min after ZAHS stimulation, maximal NF-κB activity was observed at 120 min. Pretreatment of endothelial monolayers with PDTC (20 μmol/L) significantly inhibited the secretion of IL-8 (P＜0.05). CONCLUSION:Bypass-activated complement directly challenged HUVECs to secret IL-8. Cytoplasma to nuclear translocation of NF-κB was necessary for this response.