Background: The generation of proinflammatory cytokines in platelet concentrates (PCs) by white cells is thought to be implicated in febrile nonhemolytic reactions. Furthermore, other cytokines could be generated in the PCs as signs of white cell activation when PCs are prepared from a pool of buffy coats (BCs). The number of white cells in the PCs is crucial to cytokine generation.
Study design and methods: Each of the PCs (n = 12) was prepared from a pool of BCs from four donors. Before storage, half of the BC-derived PCs (BC-PCs) were white cell reduced by filtration. The BCs and the unfiltered and filtered BC-PCs were assayed for the presence of cytokine mRNA (i.e., interleukin [IL]-1beta, IL-6, tumor necrosis factor alpha [TNFalpha], IL-8, IL-2, and interferon gamma [IFN-gamma]) by the use of competitive reverse transcription-polymerase chain reaction.
Results: No mRNA of cytokines with pyrogenic activity, that is, IL-1beta, IL-6 and TNFalpha, was detected in either the filtered or the unfiltered BC-PCs. Likewise, IL-2 mRNA was not found in any of the BC-PCs. IFN-gamma mRNA, however, was detected in the unfiltered BC-PCs but not in the filtered BC-PCs. IL-8 mRNA was found in both the unfiltered and the filtered BC-PCs, but with a lower frequency in the filtered BC-PCs.
Conclusion: The unfiltered BC-PCs produced in the top-and-bottom bag system contain traces or undetectable levels of the investigated cytokine mRNA. The results can be used in defining consensus recommendations for the use of filtered and unfiltered blood components.