Isolation of leukemic blasts from peripheral blood by density gradient centrifugation.

Abstract A method of separating human leukemic blasts from the other cell types in the peripheral blood by density gradient centrifugation is presented. The erythrocytes and granulocytes are largely removed in a preliminary centrifugation step or by sedimentation in an inverted syringe and subsequent freezing at a rate of 1 ° C. per minute. The leukemic cells are then isolated on Ficoll linear density gradients by rate zonal or isopycnic centrifugation. Dye exclusion tests with trypan blue demonstrate 85 to 100 per cent viability of the separated cells. This technique can be adapted to obtain pure populations of viable leukemic cells in quantities sufficient for biochemical, immunologic, and metabolic studies.