Erythrocyte membrane topo-optical staining reflects glycoprotein conformational changes

The study is concerned with the relationship of induced birefringence to conformational alterations of glycocalyx glycoproteins. Human erythrocytes washed with phosphate-buffered saline (PBS) and fixed with glutaraldehyde exhibit the most intense topo-optical staining, which is thought to reflect the lipid bound state of glycophorins. Incubations at reduced pH, in hypotonic media or in the presence of procaine resulted in a significant decline of induced anisotropy. The effects were not due to degradation of glycocalyx constituents. Erythrocytes subjected to treatments with procaine or at pH 6x2 suffered from loss of electrophoretic velocity, a finding indicative of rearrangement of cell surface glycoproteins. by example of the red blood cell the findings of this study confirm the premised suggestion of the sensible detection by topo-optical toluidine blue staining of the conformational state of glycoproteins of the glycocalyx.