Red blood cells deposit membrane components on contacting surfaces

An investigation of red blood cell interactions with "foreign" surfaces is reported. Experiments consisted of flowing suspensions of washed human red cells through a packed column of either glass or siliconized glass beads. Conditions were chosen so that hemolysis was minimized. The column was washed to remove suspended red blood cells and then eluted. Samples of beads were examined by SEM after washing and before elution. The eluate was examined by UV/visible spectroscopy and SDS-PAGE; for both types of packing it was found to contain cell membrane components. It is therefore concluded that membrane material is deposited on the bead surface as the cells flow through the column. The SDS-PAGE data show that membrane skeleton proteins are essentially missing from the eluate, while SEM examination indicates the presence of filamentous deposits on the bead surfaces. These data suggest that cell-surface interaction may occur through a tether-type mechanism involving extrusion of part of the membrane including the integral membrane proteins.