(19c) The Effect of Rigid Red Blood Cells on Platelet Adhesion in Blood Flow: Potential Implications in Sickle Cell Disease
Materials and methods: We utilized an in vitro flow-based system to examine how the extent of rigidification and rigid RBC concentration affect platelet margination and binding to a damaged endothelium model mimicking acute vascular damage. RBCs were removed from the whole blood and artificially rigidified using a peroxide solution. The RBCs were then reconstituted into blood and perfused over the damaged endothelium using a parallel plate flow chamber (PPFC) in a variety of different blood flow patterns and conditions. Platelet adhesion was quantified using fluorescent microscopy and compared to a healthy control.
Results and conclusions: The presence of rigid RBCs in flow drastically increases platelet adhesion under a variety of rigidities and concentrations and is dependent on variables including extent of RBC rigidity, shear rate, and flow pattern. This finding suggests that rigid RBCs may play a major role in disrupting normal hemodynamics and contributing to the pervasive vaso-occlusive crises that occur in many SCD patients. Overall, we will elucidate how rigid RBC-platelet interactions affect platelet binding, a critical step in hemostasis. This study can help determine the mechanism causing vaso-occlusive events in SCD patients and can form the basis of the study of platelet-cell dynamics in the future.