Computational Identification and Characterization of New microRNAs in Human Platelets Stored in a Blood Bank

Platelet concentrate (PC) transfusions are widely used to save the lives of patients who experience acute blood loss. MicroRNAs (miRNAs) comprise a class of molecules with a biological role which is relevant to the understanding of storage lesions in blood banks. We used a new approach to identify miRNAs in normal human platelet sRNA-Seq data from the GSE61856 repository. We identified a comprehensive miRNA expression profile, where we detected 20 of these transcripts potentially expressed in PCs stored for seven days, which had their expression levels analyzed with simulations of computational biology. Our results identified a new collection of miRNAs (miR-486-5p, miR-92a-3p, miR-103a-3p, miR-151a-3p, miR-181a-5p, and miR-221-3p) that showed a sensitivity expression pattern due to biological platelet changes during storage, confirmed by additional quantitative real-time polymerase chain reaction (qPCR) validation on 100 PC units from 500 healthy donors. We also identified that these miRNAs could transfer regulatory information on platelets, such as members of the let-7 family, by regulating the gene, which is a deubiquitinating enzyme highly expressed in platelet hyperactivity. Our results also showed that the target genes of these miRNAs play important roles in signaling pathways, cell cycle, stress response, platelet activation and cancer. In summary, the miRNAs described in this study, have a promising application in transfusion medicine as potential biomarkers to also measure the quality and viability of the PC during storage in blood banks.