[Potentially pathogenic changes in red blood cells during their storage]

Blood fractionation and storage improve the availability of blood products, e.g., packed red blood cells (RBCs) for transfusion. But the following question appears: how long-stored RBCs are safe and effective? In many clinical retrospective studies authors indicated risk of transfusion of stored RBCs, especially in critically ill patients eg. with acute myocardial infarction syndrome. They observed higher frequency of mortality, morbidity, infections, renal and lung failure, inflammation and thrombosis when RBC units were long-stored and non-leucoreduced than when they were fresh and leucoreduced. Responsible mechanisms are unknown but some factors are suspected eg.: RBCs do not deliver oxygen, because they have low concentration of ATP and 2.3 DPG and their shape changes. Also cytokines, enzymes and ions (K, Ca) from white blood cells (WBCs) can influence RBCs and transfused patients. Changes involve some membrane molecules associated with adhesion, oxygen transport, complement regulation during the storage of RBCs. It is interesting how the long-period storage and presence of WBCs can influence the membrane surface of RBCs and then their biological functions. Proposed study can improve our knowledge about changes in RBCs during their storage and then may be safety of blood transfusion.