Characterization Of The Interactions Of Staphylococcus aureus With Endothelial Cells In A Shear Environment

Kesav Reddy and Dr. Julia Ross
University of Maryland, Baltimore County
ECS 102, 1000 Hilltop Circle
Baltimore, MD - 21250
kreddy1@gl.umbc.edu
(410) 455-3435
 

Staphylococcus aureus (S.aureus) is an opportunistic pathogen causing life - threatening infections, which include endocarditis, osteomyelitis and septic arthritis. Due to the continued rise in the incidence of antibiotic - resistant infections of S.aureus, there is a pressing need to elucidate the molecular mechanisms of the pathogenesis of S.aureus infections. An intriguing aspect of this infection is the frequency of hematogenous spread of the organism from local sites of infection to deeper tissues, much akin to tumor metastasis. This suggests that an understanding of the interaction of S.aureus with the endothelium, which forms the blood wall, is required. However all studies in literature involve static assays in which S.aureus is incubated with endothelial cells leading to adherence to the endothelial cells. These assays ignore the effect of drag forces present at the blood vessel wall. Shear stresses may lead to selective molecular mechanisms of interaction and also, possibly modulate the kinetics of binding of the bacteria to endothelial cells. The development of a dynamic assay involving the perfusion of S.aureus over endothelial  cells at defined shear stresses in parallel plate flow chambers and characterization of the resulting interactions by video microscopy and digital image processing is described.