Evaluation of small noncoding RNAs in ex vivo stored human mature red blood cells: changes in noncoding RNA levels correlate with storage lesion events.

While biomarkers of storage lesions (SLs) for red blood cells (RBCs) abound, the physiologic consequences of SLs and associated important events are poorly understood. Previously we have identified differentially expressed regulatory small noncoding RNAs (ncRNAs) in stored RBCs, suggesting their role in the RBC SL process and their potential as quality biomarkers of stored RBCs. Comprehensive ncRNA expression analysis of RBCs stored for up to 56 days was performed on RNAs collected from enriched mature RBCs on Days 0, 7, 14, 28, 42, and 56. Three known RBC SL processes, that is, mature RBCs' suicidal death (eryptosis), ATP loss, and changes in RBC indices, were correlated with differentially expressed ncRNAs to gain knowledge on the SL molecular processes. The analysis identified four ncRNAs whose changes in the expression levels were correlated with the selected three SL processes. Differential expression on Days 14 and 28 of the four selected ncRNAs was confirmed by TaqMan quantitative reverse transcription-polymerase chain reaction analysis. Bioinformatics analysis identified potential targets and biologic functions of these ncRNAs. Overexpression of one such ncRNA, hsa-miR-196a, in a human erythroblast cell line confirmed its protective effects against the cell death and ATP loss. Overall, this study demonstrates that changes in the levels of small ncRNAs of stored RBCs correlate with some of the SL events and thus they have the potential to serve as the storage quality markers.