Electrical sizing of particles in suspensions IV. Lymphocytes

The factors involved during the pumping of a particle suspended in an electrolyte through a small cylindrical orifice across which exists an electric field are reviewed, and their practical application to cell volume measurement in terms of orifice geometry and particle properties is considered. Procedures are described to determine whether a particular cell type satisfies the operational criteria of a rigid, non‐conducting sphere, for which the theoretical expressions can be reduced to an especially simple form under appropriate conditions. Experimental results are presented for the case of chick, mouse and human lymphocytes, all of which are shown to satisfy the above requirements. Volume distributions are provided for chick blood lymphocytes and compared with those from various lymphatic organs; representative data are also reported for different types of mouse lymphocytes. Human blood lymphocytes are found to have normally‐distributed diameters (p > 98%), a property not shared by their volumes or their surface areas, nor by blood lymphocytes from the chick or from patients with chronic lymphatic leukemia. A possible implication of this finding is mentioned briefly.