Red cell storage lesion: the potential impact of storage-induced CD47 decline on immunomodulation and the survival of leucofiltered red cells.

Red blood cells undergo major biochemical and biomechanical changes during storage that could effect their post transfusion performance. Biochemical effects include changes in 2,3-diphosphoglycerate (2,3-DPG), ATP, and calcium levels, as well as metabolic modulation and release of Annexin V, a cytosolic component of blood cells, as a global marker of cellular injury and fragmentation. Biomechanical changes include alterations in cellular membrane, shape changes, phospholipid content, phospholipid asymmetry, and antigenic markers. Although the extent of these changes under various storage conditions has been well documented, their clinical effects remain unclear. In the current era of universal leucodepletion, the immunomodulatory effects of some essential markers such as CD47 and phosphatidyl serine become the focus of interest as highlighted in this manuscript.