Preparation of leukocyte-depleted platelet concentrates from apheresis platelet rich plasma filtered using a triple-bag system with a filter.

Transfusion of leukocyte-depleted platelet concentrates prevents or delays HLA immunization in multitransfused patients. The authers devised a polyvinylchloride triple-bag system with a filter for preparation of leukocyte-depleted platelet concentrates (PC) from apheresis platelet-rich plasma (PRP). We spliced a Imugard PL filter (Terumo Corporation) into the tubing between the primary 1-liter bag and the second 1-liter bag using a sterile connection divice (SCD). Apheresis PRP was filtered through the Imugard PL in a closed system by gravity with neither priming before filtration nor rinsing after filtration.The platelet recovery was 94.4±3.8% and leukocyte removal was 99.8±0.4%. The functions of platelet were not affected by the filtration. The filtered PRP was then centrifuged and yield leukocyte-depleted PC and plasma for freezing as fresh-frozen plasma. PC was stored in the 1-liter bag at 22°C with flatbed agitation for up 96 hours of storage. Mean platelet count did not change during the storage. pH, collagen-induced platelet aggregation response and plasma LDH activity became significantly higher than that in the ordinary PC.% HSR, MPV and morphology score were approximately the same in comparison with the ordinary PC. It may be concluded that the method is effective in preparing leukocyte-depleted PC from apheresis RPR.