Effects of Shear Stress, Acridine Orange and Zn²⁺ on the Shape of Red Blood Cells and Their Aggregation in Autologous Plasma and Dextran Solution

The process of erythrocyte aggregation in autologous plasma and 3% dextran 70 solution was studied by light microscopy (1000x). When a suspension of washed erythrocytes is placed between two glass surfaces, they lose their biconcave discoidal shape and turn into echinocytes. After adding autologous plasma to echinocytes and intensive agitation, they are converted into discocytes, and then into stomatocytes. After that, the stomatocytes were combined into aggregates in the form of rouleaux. The addition of saline solution to the aggregates of red blood cells in autologous plasma led to cell disaggregation. At the same time, the appearance of stomatocytes from aggregates was observed. The addition of dextran 70 solution to echinocytes did not lead to their aggregation. At the same time, the addition of albumin to echinocytes restored the discoidal shape of the cells and turned them into stomatocytes. It was found that after adding dextran 70 solution to the stomatocytes, their strong aggregation occured. Treatment of echinocytes with trypsin did not restore the shape of red blood cells, but caused strong aggregation of echinocytes induced by dextran 70. A possible mechanism of erythrocyte aggregation is discussed.