Correlation between the oscillatory and adhesion activities in erythroid cells

The attachment kinetics of erythroid cells, such as human erythrocytes, the ir saponin ghosts, and erythroleukemia cells K562, to a glass surface has b een studied in the presence of substances inhibiting spontaneous fluctuatio ns of cellular membranes. It has been shown that wheat germ agglutinin (WGA ) slows down the attachment kinetics of K562 cells, as it occurs in the cas e of intact erythrocytes., Concanavalin A (ConA), which inhibits the attach ment of erythrocytes to glass does not affect the adhesion of K562 cells to glass due to the absence of Band III proteins in the membranes of K562 cel ls. Both lectins slow down the adhesion rate of saponin ghosts of human ery throcytes, as it takes place in intact erythrocytes. Suramin and the anioni c dye ANS bind specifically to the actin protofilaments of the erythrocyte skeleton and inhibit cell adhesion to glass,as well. At the same time, thes e substances do not affect the oscillatory and adhesion activities of intac t erythrocytes due to the impermeability of erythrocyte membranes for these drugs. The obtained results allow the conclusion that inhibition of erythrocyte ad hesion by lectins is due to lectin binding to different constituents of the erythrocyte membrane - sialic acid moieties of glycophorin in the case of WGA and Band III proteins in the case of ConA. The most probable mechanism of erythrocyte and K562 cell: attachment to glass is formation of the so-ca lled local contacts between the cells and a glass surface. It can be suppos ed also that the cell surface oscillations facilitate cell contact formatio n.