A sluicing device for reproducibly measuring the strength of attachment of cultured cells to their substrate

We assessed the strength of attachment of cultured human vascular endothelial cells to tissue culture plastic by controlled sluicing of cells, grown on multiwell plates, with isotonic saline using a specially designed nozzle attached to a reciprocating pump. Cells which were not dislodged were trypsinized and counted. The percentage of cells dislodged was proportional to the pump speed and to the volume of saline pumped. For given pump settings the proportion of cells detached was reproducible. The percentage of cells detached by sluicing increased at lower cell densities and decreased when the duration of trypsinizing of cells to be plated in multiwells, prior to sluicing, was increased. Our system is suitable for evaluating effects of biochemical interventions on the strength of cell attachment to the substrate.