DIFFERENTIAL REDUCTION IN LYMPHOCYTE AND GRANULOCYTE CONTENT BY REMOVAL OF THE BUFFY COAT FROM FRESH AND OVERNIGHT-STORED BLOOD - COMPARISON OF MANUAL AND AUTOMATED BLOOD PROCESSING SYSTEMS

The efficiency of leukocyte removal was studied by the removal of the buffy coat layer from fresh and overnight-stored whole blood. Manual b lood processing was compared with two types of automated separators: t he T-ACE (Terumo) and the OPTI system (with the top-and-bottom bag, Ba xter). The main characteristics of leukocyte removal were similar for the systems studied. The efficiency of leukocyte removal was consisten tly higher with overnight-stored blood. When the net red cell content of the buffy coat was 20-30 mt, the figures were: 70% (n=103) vs 45% ( n=87, manual method), 78% (n=6) vs 60% (n=100, T-ACE) and 82% (n=10) v s 71% (n=20, OPTI system), respectively. The increase in the efficienc y in leukocyte removal was due to a rapid increase in the efficiency o f removal of granulocytes: 65% (n=65) vs 45% (n=57, manual method), 80 % (n=4) vs 46% (n=83, T-ACE) and 74% (n=9) vs 57% (n=17, OPTI system), respectively. Processing of overnight stored blood may provide red ce ll concentrates with fewer contaminating leukocytes and granulocytes. (C) 1997 Elsevier Science Ltd.