Study of the Role of Interferon αon the Endothelial Dysfunction During Septic Shock

Septic shock is the most severe form of a bacterial infection, affecting 24 million patients per year worldwide, with a high mortality (\> 30%). Septic shock is defined by an acute circulatory failure, with low blood pressure and insufficient oxygen supply to organs. This circulatory failure is related to vascular damages, in which the endothelial vascular tissue is impaired by inflammatory mechanisms, with release of circulating endothelial cells in the blood. Therefore, modulating inflammation on the vascular endothelial tissue could be a therapeutic strategy, and the investigators focus on the role of the type I interferons on the endothelial tissue because of the demonstrated role of type I interferons during septic shock. Thus the investigators proceed to an observational study, in which the primary purpose will be to show a higher expression of type I interferon receptors on circulating endothelial cells in patients with septic shock compared to control subjects. Concerning secondary purposes, the investigators will record mortality at d3, d7 and d28, perform assays about types I, II and III interferons in plasma, and test anti-interferon on endothelial cells ex vivo