ИСТИНА

Laser trapping systems provide a convenient and very effective opportunity for assessing the mechanisms of interaction on the level of single cells and/or macromolecules. In this study, laser tweezers (LT) were used for trapping the red blood cells (RBC) and measuring the interaction forces between them for studying the process of the RBC aggregation. Spontaneous aggregation of RBCs takes place both in vivo and in vitro and leads to the formation of first linear and then 3D aggregates, which can be disassembled (disaggregated) when shear stresses in the flow or other external forces are applied. RBC aggregation significantly influences the blood viscosity at low shear stress conditions and affects the blood circulation throughout the body. With the perspective for the clinical application a number of methods were developed for the quantitative assessment of this property. The most advanced techniques that are used nowadays are based on measuring the intensity of the laser beam scattered by a blood sample in vitro or analyzing the microscopic images of a large group of RBCs placed upon a glass plate. However, these methods do not provide the details of the cells interaction. Recently the LT were introduced to this research and were shown to be a promising tool for the further assessment of the RBC aggregation. In particular, LT could characterize the cells interaction strength, which cannot be measured with the conventional methods.