The influence of shear stress on adhesion of methicillin-resistant Staphylococcus aureus to human endothelial cells

Methicillin-resistant Staphylococcus aureus is an increasingly prevalent pathogen capable of causing severe vascular infections. Infection is thought to be initiated when circulating bacteria firmly adhere to the endothelium. Local hydrodynamics are known to strongly influence endothelial function, yet the impact on endothelial interactions with MRSA remains highly unknown.;Using an in vitro model of the vasculature and confocal microscopy, I have shown that MRSA adhesion to endothelial cells decreases with increasing shear stress. It was demonstrated that shear stress preconditioning of the endothelium prior to infection also reduces adherence. However, shear rate and fluid viscosity did not appear to play a critical role. Results further suggested that the shear stress distribution over the surface of an individual endothelial cell may affect the local deposition of bacteria. In conclusion, this study provides evidence that bacterial binding to the endothelium is influenced by characteristics of the flow to which it is exposed.