• Takashi Miyoshi, Kouhei Yamashita, Toshiyuki Arai, Kokichi Yamamoto, Kiyomi Mizugishi, and Takashi Uchiyama.
• Department of Haematology and Oncology, Kyoto University Hospital, Sakyo-ku, Kyoto, Japan.
• Immunology. 2010 Nov 1; 131 (3): 331-9.

AbstractSepsis is a generalized inflammatory disease, caused by the hyperinflammatory response of the host, rather than by invading organisms. Endothelial cells play a crucial role in the pathogenesis of sepsis. In this study, we investigated the effects of interleukin-8 (IL-8), a known neutrophil chemoattractant, on lipopolysaccharide (LPS) -induced reactive oxygen species (ROS) production by endothelial cells, and its significance in the pathogenesis of LPS-mediated sepsis. The results revealed that IL-8 directly induced ROS production in human umbilical vein endothelial cells (HUVECs), and also mediated LPS-induced ROS production by HUVECs. Stimulation of HUVECs by LPS strongly enhanced tissue factor expression, a hallmark of severe sepsis, which was suppressed by IL-8 knockdown. We further discovered that NADPH oxidase (Nox) 1 expression in LPS-stimulated HUVECs was markedly repressed by IL-8 knockdown, and Nox1 knockdown reduced tissue factor expression, suggesting that the LPS/IL-8 signalling in endothelial cells was predominantly mediated by Nox1. In conclusion, LPS stimulation of endothelial cells causes activation of the IL-8-Nox1 axis, enhances the production of ROS, and ultimately contributes to the progression of severe sepsis.© 2010 The Authors. Immunology © 2010 Blackwell Publishing Ltd.

37 keywords...

hide…