Force Transmission across the Endothelial Glycocalyx

The glycocalyx is an interfacial biomaterial found on the surface of a wide variety of cell types. This matrix plays an active role in defining the mechanical and biochemical environment of living cells. In addition, it is directly involved in the detection of mechanical stimuli in the cellular environment, such as the shear stress in the blood vessel wall. As an incredibly low-density soft material the glycocalyx has proved a challenging target to probe experimentally. In this work, we describe our efforts to measure the force transmission across the glycocalyx in the presence of time varying fluid flow. Strain in a soft deformable substrate is measured in the presence of sinusoidal fluid flow as a biomimetic glycocalyx comprised of hyaluronan and charged proteoglycans is grafted to its surface. We investigate the effect of these major structural elements of the glycocalyx on measured strain on the substrate. The results may point toward a potential physical mechanism for the involvement of the hyaluronan-rich glycocalyx in the detection of shear flow at the cell surface.