Figure 11.

Selected results from studies involving technologies that leverage platelet’s bleeding site-selective adhesion mechanisms. 11A shows platelet aggregometry studies to demonstrate that addition of rGPIbα-decorated albumin microsphere particles significantly enhances the aggregation level of platelets in presence of vWF and ristocetin, compared to without ristocetin, thereby confirming that the aggregation enhancement is due to the binding of rGPIbα to ristocetin-induced unfolded vWF; 11B shows that polystyrene microparticles surface-decorated with vWF’s A1 domain or platelet’s GPIbα fragment can undergo shear-responsive enhanced adhesion on GPIbα–coated or vWF-coated surfaces respectively, under flow, mimicking platelet-relevant adhesion mechanisms; 11C shows an experimental schematic of flowing rGPIbα-decorated red fluorescent liposomes over vWF-coated surfaces, with the corresponding fluorescence microscopy results demonstrating enhanced adhesion and accumulation of these liposomes over time at higher shear, mimicking the shear-responsive interaction of platelet GPIbα to vWF. Figure components adapted and reproduced with permission^[413,414]. Copyright 2012, John Wiley & Sons Inc. and 2000, American Chemical Society.