Ficoll flotation for the separation of blood leukocyte types.

T SHOULD BE POSSIBLE to separate cells of different types by utilizing differences in their specific gravities. Centrifugation of whole blood against high density fluids has been successful, at least in part, in separating leucocytes from peripheral blood.15 Gum acacia3 and bovine albumin1’2’5 have been used in this manner, but the method has been criticized because of the cost and labor involved in preparing the media, and doubts have been expressed as to the viability of the cells isolated.6 We have reported previously7 the use of Ficoll as a density fluid for the isolation of leukocytes from peripheral blood. It is inexpensive, stable and appears to be nontoxic to cells. The present paper describes further experiences with, and some modifications of the method, which illustrate the usefulness of Ficoll far separation of cells by the flotation method.