FORUM EKSPERTÓW
A nanoscale resolution assay of flow-induced platelet microaggregation

Background: Platelet aggregation is essential for vascular haemostasis and thrombosis. Inhibition of platelet aggregation underpins the pharmacological and clinical effects of antiplatelet drugs. These effects are commonly quantified using methods that assess platelet aggregation under no-flow conditions in macroscale. These devices neither mimic the conditions found in human microvasculature nor detect microaggregates.

Aim: The aim of our study was to develop a new method of flow-induced platelet microaggregation using a commercially available (Q-SenseTM E4 system) nanoscale resolution device, Quartz Crystal Microbalance with Dissipation (QCM-D), that measures mass deposition on sensor crystals as changes in their frequency of vibrations f and energy dissipation D.

Material and methods: Human platelets were perfused through QCM-D and f and D were recorded in real time. Phase-contrast, confocal imaging, atomic force microscopy and flow cytometry were also used to study flow-induced platelet microaggregate formation on the surface of fibrinogen-coated crystals.

Results: Microaggregates were detected by the device by changes in f and D in a platelet concentration-, flow- and shear stress-dependent manner, confined to the sensor surface and imaged by phase-contrast, confocal and atomic force microscopy.

Conclusions: QCM-D is a sensitive device capable of measuring flow-induced platelet microaggregation.