Removal of anaphylatoxins C3a and C5a and chemokines interleukin 8 and RANTES by polyester white cell-reduction and plasma filters

BACKGROUND: A few bedside polyester white cell (WBC)-reduction filters have been shown to scavenge C3a anaphylatoxin from stored blood components. One has been shown to remove the chemokines interleukin (IL)-8 and RANTES, but not the proinflammatory cytokines IL-1, IL-6, and tumor necrosis factor alpha. Removal by any filter of the anaphylatoxin C5a or the soluble membrane attack complex (SC5b-9) has not been studied. Further, the ability of other filters to scavenge these biologic response modifiers (BRM) is not known. Four WBC-reduction filters and one plasma filter were studied for their ability to remove IL-8, RANTES, IL-1 beta, C3a, C5a, and SC5b-9. STUDY DESIGN AND METHODS: Plasma was obtained either as freshly thawed fresh-frozen plasma, fresh-frozen plasma thawed and stored for 5 days, or platelet-poor supernatant. Cell-poor plasma was obtained and samples were taken before and after filtration through the various filters. Levels of IL-1 beta, IL-8, RANTES, C3a, and SC5b9 were quantitated by enzyme immunoassay. To evaluate filter scavenging of C5a, an in vitro model was developed to generate high levels of C5a in plasma by activating plasma with zymosan. RESULTS: Levels of C3a, C5a, IL-8, and RANTES were reduced by filtration through two bedside platelet WBC-reduction filters, a plasma filter, and a prestorage red cell WBC-reduction filter, but not following filtration through a prestorage platelet WBC-reduction filter. For some BRMs and filters, however, evidence of filter saturation was seen. IL-1 beta was not removed by any of the filters tested. CONCLUSION: Some, but not all, bedside polyester filters and prestorage polyester filters can remove IL-8, RANTES, C3a, and C5a from units of plasma or platelets. Improved biomaterial engineering of these and other filters could maximize scavenging of BRMs and potentially diminish the adverse reactions associated with their infusion during transfusion.