A prospective observational study of the effect of platelet transfusions on levels of platelet-derived cytokines, chemokines and interleukins in acute leukaemia patients with severe chemotherapy-induced cytopenia.

BACKGROUND Platelet concentrates contain soluble mediators derived from both platelets and contaminating leukocytes. During platelet transfusion these mediators are transferred, and transfusion-induced modulation of the cytokine network may then occur, possibly contributing to transfusion reactions, immunomodulation, or affecting residual leukemic cells. In this prospective observational study, we investigate the effect of platelet transfusion on the systemic levels of platelet-derived cytokines, chemokines and interleukins in an unselected group of acute leukaemia patients with severe chemotherapy-induced cytopenia. STUDY DESIGN AND METHODS We investigated 31 platelet transfusions involving pre-storage, white blood cell-reduced, gamma-irradiated or pathogen-inactivated, photochemically-treated platelet concentrates received by 10 unselected patients. Peripheral blood plasma samples were collected before, immediately after, one hour, and 24 hours after the transfusions. Sampling from platelet concentrates was performed immediately before transfusion. A total of 31 soluble mediators were examined. Ten healthy controls matched for age and gender were included. RESULTS Despite heterogeneity in patients and platelet concentrates, significantly increased plasma concentrations were detected for the platelet-derived mediators, platelet-derived growth factor, β-thromboglobulin, transforming growth factor-β (TGF-β), CCL5, and CXCL4, 1 hour and/or immediately after platelet transfusions. The plasma levels of vascular endothelial growth factor and soluble CD40 ligand were not altered by platelet transfusion. Certain interleukins (IL-1β, IL-2, IL-4, IL-6, IL-9, and IL-12), as well as interferon-γ showed a minor, transient decrease in systemic plasma levels during the first hour following transfusion. CONCLUSION Platelet transfusions modulate the systemic cytokine network in acute leukaemia patients with severe, chemotherapy-induced cytopenia.