Abstract: Studies were carried out to determine the efficacy and validity of utili zing flow cytometric technics (Coulter principle) for quantitatively assessing the tendency for erythrocytes to aggregate in suspension. Dextran, a neutral polymer, was used at a variety of concentrations as a model aggregating agent. The results, expressed in terms of an aggregation value (AW), were found to correlate well with those obtained by low shear viscometric technics in which the relative apparent viscosity ratio, R, was previously shown to be a quantitative and reproducible index of cellular aggregation. These results, taken together with the recently shown correlation of the AW with pathophysiological circulatory disorders such as coronary artery disease, as well as the simplicity of the methods described, provide a sound basis for utilizing flow cytometry in diagnostic screening programs.
