A New Method for Preparing Buffy Coat‐Poor Blood

Patients who have been sensitized to leukocytes by transfusions and pregnancy are subject to “pyrogenic” reactions of varying severity following the administration of whole blood. Present methods for preparing buffy coat‐poor blood utilize differential centrifugation or sedimentation in the presence of dextran. They are time consuming and not uniformly dependable. The procedure described removes the granulocytes from heparinized whole blood by passing it over a column of Nylon fibers in ten to 15 minutes. Only 5 per cent of the donation is retained in the column and the white blood counts of the final product are 500‐3,100/cu. mm. with 95 to 100 per cent lymphocytes. Cr 51 survival studies suggest that these preparations withstand storage satisfactorily for 14 to 21 days. Our experience with the transfusion of 82 units of this product and the relative importance of lymphocytes and granulocytes in leukoagglutination are discussed.