Blood flow profiles at atheroprone sites of arteries generate a relatively low and oscillating wall shear stress acting on the endothelium. Monocytes are recruited to these sites by involvement of CXC cytokines. Therefore, this study was done to reveal the influence of different flow profiles on the expression of CXC-cytokines by endothelial cells. Human umbilical vein endothelial cells (HUVEC) were exposed to shear stress for 24 h in a cone-and-plate system either generating an atheroprone or atheroprotective flow profile. The expression of CXCL1, -2, -3, and -8 was analysed using standard protocols for quantitative real time RT-PCR and by commercially available ELISAs. All cytokines tested were induced by the atheroprone flow profile about ten times above control levels in HUVEC cultured without flow which was comparable to the effect achieved with TNFa (100 U/ml). By contrast, cytokine expression was significantly reduced in endothelial cells exposed to an atheroprotective flow profile compared to control cultures without flow. These data support the hypothesis that flow-dependent regulation of endothelial CXC-cytokine expression contributes to facilitate monocyte recruitment to the vessel wall at sites with disturbed (low and oscillating) blood flow.