Use of white cell counts to select units of whole blood for granulocyte preparation

Multiple variables that are easily determined, including donor white cell count, were studied for possible value in selecting single units of whole blood for isolation of granulocytes. Whole blood units selected on the basis of total white cell count were shown to have a 78 percent greater granulocyte content than randomly selected units (3.0 X 10(9) granulocytes/unit vs. 1.7 X 10(9) granulocytes/unit, p less than .001). White cell counts determined on 5-hour-old segments of whole blood were demonstrated to have a high coefficient of correlation with white cell counts determined on freshly drawn EDTA specimens (r = 0.918) and fresh segments of whole blood (r = 0.926). We conclude that yields of granulocytes from single units of whole blood stored for up to 5 hours at room temperature can be increased by selecting units with high total white cell counts performed on blood unit segments.