Cytokine generation in whole blood, leukocyte-depleted and temporarily warmed red blood cell concentrates

Background and Objectives: It has been suggested that inflammatory cytokine s such as Interleukin (IL)-1 beta, IL-6, tumor necrosis factor-alpha (TNF-a lpha) and IL-8 might be responsible for a large number of non-antibody-medi ated adverse reactions to the transfusion of blood components, especially o f platelet concentrates (PCs). The aim of this study was to compare the lev els of proinflammatory cytokines in different blood components containing r ed cells such as buffy-coat-free packed red cells (RBCs), filtered RBCs and whole blood (WB) during storage under several conditions. Materials and Me thods: WE (CPD-A1, n = 16) was stored for 35 days at 2-6 degrees C; samples were taken on days 0, 21 and 35. Buffy-coat-poor RBCs in additive solution PAGGS-M (n = 16) were divided into halves, one half was leukocyte (WBC)-de pleted by filtration on day 0, both halves were stored for 49 days at 2-6 d egrees C (samples: days 0, 21, 49). Furthermore, buffy-coat-poor, unfiltere d SAG-NI RBCs (n = 16) were halved immediately after production and stored at 2-6 degrees C until day 42 (samples: days 0, 21, 42). One half remained at room temperature for 24 h on day 3. Cytokine levels were determined with commercial enzyme-linked immunosorbent assays. Results: Levels of IL-1 bet a and TNF-alpha rose during storage of WE and RBCs. IL-6 could be detected markedly above the detection threshold in WE only. At the end of storage, w e detected IL-8 in 1 of 16 units of WE tested, in 10 of 16 standard PAGGS-M RBCs and in 15 of 16 temporarily warmed SAG-M RBCs. Prestorage filtration of RBCs prevented the accumulation of IL-1 beta and TNF-alpha. Temporarily warming of RBCs for 24 h did not cause any substantial increase in cytokine levels other than IL-8. RBCs stored in different additive solutions (PAGGS -M versus SAG-M) showed similar cytokine concentrations during storage. The cytokine content of WE was very similar to that of buffy-coat-poor RBCs. C onclusion: Cytokine levels measured in WE and buffy-coat-poor RBCs result i n levels which are unlikely to cause febrile reactions even in the case of massive transfusion. We conclude that, according to present knowledge, ther e is no reason for prestorage filtration of buffy-coat-poor RBCs or WE to a void febrile transfusion reactions due to cytokine accumulation during stor age.