Plasma was sampled at baseline , 6 hours , and 24 hours after randomization or transfusion , and concentrations of interleukin ( IL ) -1 , IL-2 , IL-4 , IL-5 , IL-6 , IL-8 , IL-10 , IL-12-p70 , interferon - , tumor necrosis factor - , human neutrophil elastase , soluble L-selectin , and C-reactive protein were measured using cytokine bead array analysis and an enzyme-linked immunosorbent assay .