Influence of flow velocity and cell concentration on dynamic adhesion of erythrocytes to glass surface

Comparative studies were carried out on dynamic adhesion of 51Cr-labelled erythrocytes to the surface of glass beads in the presence of serum in the medium (50 microng of protein/ml) and in protein-free medium. The influence of cell concentration (within the range 4 X 10(5) to 8 X 10(6)/ml) and of cellular flow velocity (within the range 1.5-0.4 cm/min) on the value of adhesion was investigated. It was found that when serum was present in the medium, the decisive influence on erythrocyte adhesion was exerted by the velocity with which the cells pass though the glass bead layer. Cell concentration under these conditions has only a very slight effect. When the medium does not contain serum, erythrocyte adhesion to the bead layer seems to depend on both cell concentration and flow velocity. Preliminary data were obtained concerning the release of 51Cr from the bead layer after erythrocyte adhesion.