Method for processing leukocyte- and platelet-poor red cells in closed bags.

If leukocyte- and platelet-poor red cells have been processed and stored in closed bags, their delivery, especially on holidays, will be easy. The modified warm-centrifuge method was applied to a quadruple bag prepared for such purpose. Red cells were processed in the first bag by the centrifugation of whole blood. The supernatant plasma was transferred to the second bag. A phosphate buffer in the third bag was introduced into red cells and diluted red cells were then incubated at 37 degrees C for 1 h in an inverted position. After centrifugation, the red cell phase below the buffy coat layer was isolated using a Biotest separation apparatus and stored in the fourth bag (containing a preservative with adenine, phosphate, glucose and 0.9% NaCl solution) for 28 days at 4 degrees C. Ninety-eight percent of the leukocyte and 97% of platelets in whole blood unit were removed with a red cell recovery of 86%. Biochemical changes in stored red cells were similar to those of conventional buffy coat-removed red cells suspended in the same preservative, except for rapid decreases in 2,3-diphosphoglycerate levels. Since processing buffy coat-removed red cells containing few leukocytes and platelets with the present method was simple and these units might be stored for over 14 days with minimum cell damage, we suggest that the present method is useful way of processing leukocyte- and platelet-poor red cells in blood centers.