Release of cytokines in stored whole blood and red cell concentrate: Effect of leukoreduction

Background: Storage time of blood components plays a major role in the accumulation of cytokines causing adverse transfusion reactions.

Aims: The aim was to study the trend in the levels of interleukin-6 (IL-6), IL-8, tumor necrosis factor-alpha (TNF-α) and regulated upon activation, normal T-cells expressed and secreted (RANTES) during storage of whole blood (WB) and red cell concentrate (RCC) and to study the effect of leukoreduction (LR).

Materials and methods: WB sample was taken on 0, 7, 14, 21, and between 28 and 35 days and plasma aliquots were frozen. Samples from RCC and buffy-coat depleted RCC prepared using Optipress II were collected on 0, 7, 14, 21 and between 28 and 35 days. Cytokine estimation was done using ELISA development kits. Normal range of cytokines was established using 0 day samples of WB. Statistical analysis was done using nonparametric tests.

Results and conclusion: The normal range of IL-6 was 0-23 pg/ml, IL-8 0-12 pg/ml, TNF-α 0-3 pg/ml, and RANTES 1200-2000 pg/ml. IL-6 was in normal range and showed a decreasing trend during storage. IL-8 levels increased significantly from 0 to 35 days. In RCC, the highest level was 480 pg/ml on 28(th) day. It was in the normal range in buffy-coat depleted RCC up to 28 days. RANTES level was significantly low in buffy-coat depleted RCC compared to RCC. We conclude that WB has high levels of IL-8 and RANTES. The levels of cytokines are affected by storage period and LR. Comparison of WB and buffy-coat depleted RCC shows significantly low levels of IL-6, IL-8, and RANTES in buffy-coat depleted RCC. This study emphasizes the use of red cell components instead of WB and buffy-coat depleted RCC instead of RCC.