Date/Time
Date(s) - 27/11/2013
3:30 pm - 4:30 pm

Title: Plasma Protein Induced Clustering of Red Blood Cells in Microcapillaries

Speaker: Dr. Christian Wagner

Institute: Saarland University

Location: ABB 102

Description:

The supply of oxygen and nutrients and the disposal of metabolic waste in the organs depend strongly on how blood, especially red blood cells, flow through the microvascular network. Macromolecular plasma proteins such as fibrinogen cause red blood cells to form large aggregates, called rouleaux, which are usually assumed to be disaggregated in the circulation due to the shear forces present in bulk flow. This leads to the assumption that rouleaux formation is only relevant in the venule network4 and in arterioles at low shear rates or stasis. Using a combined experimental and numerical approach, we show that despite the large shear rates present in microcapillaries, the presence of either fibrinogen or the synthetic polymer dextran leads to an enhanced formation of robust clusters of red blood cells, even at haematocrits as low as 1%. Large aggregates form even for fibrinogen concentrations within the healthy physiological range. These persistent aggregates should strongly affect cell distribution and blood perfusion in the microvasculature, with putative implications for blood disorders even within apparently asymptomatic subjects.