ИСТИНА

Red blood cell (RBC) aggregability refers to the cells' ability to form multicellular aggregates in the presence of different plasma proteins or macromolecules. Opposing forces determine the extent of aggregation by the repulsive force between the negatively charged cells, the cell-cell adhesion induced by the macromolecules, and the disaggregating flow-induced shear stress. Kinetic and dynamic features of the cells interaction can characterize the RBC aggregation process [1]. The present study is intended to examine the RBC aggregation in dextran solutions in blood plasma samples using the diffuse light scattering technique as well as on the single cell level in a highly diluted suspensions using the optical tweezers [2]. Experiments were carried out with the addition of dextran of 500 and 40 kDa molecular weight into the blood at the concentration of 50 mg/ml. Basing on the obtained results, we can conclude that dextran with the molecular weight of 40 kDa is an inhibitor of aggregation, while dextran with the molecular weight of 500 kDa is an RBC aggregation inducer. Optical methods provided handy tools to study the kinetic and dynamic peculiarities of RBC aggregation and disaggregation, which can be extremely useful for controlling and correction the blood microcirculation especially in cases of hemorheological disorders.