[Leukocyte removal in a closed system of human red-cell concentrates: a technic coupled with the automated extraction of the buffy coat using a sterile connector from a filtration kit].

A technique, integrally run in a closed system, for leucocyte depletion of human red cell concentrates is described. It associates two complementary processes: buffy-coat removal and filtration. The first step is carried out with an automated system for blood component preparation (Compomat, NPBI); its efficiency is improved by a custom made blood collection set with ACD anticoagulant solution in the primary bag. The second step is simplified by a filtration kit requiring only one sterile connection for operation (SCD 312, Dupont de Nemours) and allowing a standardised rinsing of the filter. Quality control of 33 units so prepared shows principally: --an intensive leuko-depletion (4 logs) enabling leukocyte contamination to be kept below 10(6) per unit; --a moderate red cells loss (15 ml for the first step and 20 ml for the second one). This technique provides a permanently available and very pure blood component. Moreover it offers new potential for standardisation and mastery of quality control.