Retention in glass bead columns as a measure of leucocyte adhesiveness. I. Influence of sample size and erythrocyte sedimentation.

Erythrocyte sedimentation significantly influenced test results when leucocyte retention in glass bead columns was used as a measure of leucocyte adhesiveness. In blood with elevated ESR, this influence was especially evident. Erythrocyte sedimentation highly increased leucocyte retention in vertical columns with a downward flow, whereas in slightly tilted columns with an upward flow, the retention was reduced. The error in measurements caused by erythrocyte sedimentation could be corrected by means of the haematocrit values in samples and eluates. Correction was better for results obtained with slightly elevated than with vertical columns. The granulocyte retention rates increased with increasing sample size, whereas lymphocyte retention remained constant.