Differential expression of exosomal microRNAs in fresh and senescent apheresis platelet concentrates.

What is the context? Platelet transfusion is a widely used clinical treatment, but it is not totally safe. Side effects may happen to patients who receive the "older" platelet products. Exosomes in platelet products can be transfused to patients while receiving blood. Exosomes are accumulated in platelet products during storage. MicroRNAs are one of the important cargoes in exosomes, which can be delivered to the target cells, thus affecting their functions.This study aims to investigate and analyze the differential expression profiling of exosomal microRNAs in apheresis platelet concentrates during storage, and predict the potential function of the target genes. We found out the top nine differentially expressed microRNAs got involved in positive regulation of cell proliferation and nervous system development, and mainly enriched in regulating pluripotency of stem cells signaling pathway, prolactin signaling pathway, and FoxO signaling pathway, etc.What's new? Our study is the first one to test the exosomal microRNAs in the apheresis platelet concentrates. The apheresis platelet concentrates were stored for 1 day and 5 days. Compared the two time points, we obtained the differential expression profiling of exosomal microRNAs. Based on bioinformatics analyses and qRT-PCR results, we provided nine up-regulated microRNAs which might be critical mediators to communicate with target cells after transfusing.What's the impact? This study expands our knowledge of exosomal microRNA expression profiling from apheresis platelet concentrates along different storage periods. This might be relevant to immunomodulation in post transfusion situations.