Einfluss verminderter Scherkräfte auf Entzündungsreaktionen in vitro Effekte pathologischer Strömungsbedingungen auf Leukozyten-Endothel-Interaktionen und monozytäre "Tissue-factor-Expression" in humanen Zellkulturen

During malperfusion and inflammation leukocyte adhesion is common. The purpose of this study was to examine the effects of reduced shear stress on leukocyte-endothelial interactions and subsequent inflammatory reactions such as up-regulation of tissue factor. Isolated neutrophils and monocytes were co-incubated with human umbilical venous endothelium at 0-3 dynes/cm(2) in a flow chamber. Adhesion and tissue factor expression on adherent leukocytes were examined at various flow conditions. At 2-3 dynes/cm(2) adhesion occurred only on TNFalpha-activated endothelium. Below 1 dyne/cm(2) similarly increased adhesion was also observed on non-activated endothelium. As was observed for leukocyte adhesion, these shear stress-dependent cell interactions also resulted in an up-regulation of tissue factor on adherent monocytes from non-activated co-cultures. Apart from additional activators of inflammation, reduced shear forces may directly contribute to inflammation