Cell density profile as a measure of erythrocyte hydration: therapeutic alteration of salt and water content in normal and SS red blood cells.

The incubation of red blood cells in high concentrations of sodium bicarbonate produces a net influx of salt and water resulting in the dilution of cell hemoglobin. After reinfusion into the donor, cells swollen in this manner can be readily identified in peripheral blood samples by their low density on phthalate gradients. It is proposed that this manipulation of cell water content may have therapeutic implications for sickle cell disease, since the rate of deoxyhemoglobin S gelation is retarded by small reductions in hemoglobin concentration.