Stability of whole blood in storage periods up to three days at 4°C.

The library concentrations (A), identification rate (B) and UMI ratios (C) were compared between samples stored for 1 hour and 6 hours (room temperature) and 1 day, 2 days and 3 days after blood collection. The mean miRNA expression profiles at 1 hour vs. 6 hours (D), 1 hour vs. 1 day (E), 1 hour vs. 2 days (F) and 1 hour vs. 3 days (G) were compared. MiRNAs with levels that exhibited a fold change greater than 2-fold or less than half-fold are indicated outside of the dashed lines. The X-axis or Y-axis of the scatter plot indicates log2(miRNA expression counts). The Venn diagram indicates that the levels of 15 miRNAs were aligned across samples obtained from all tubes, while 1 and 25 miRNAs exhibited increased levels only at 2 days or 3 days, respectively (H). The expression levels of hsa-miR-451a (I), an indicator of hemolysis, and hsa-miR-126-3p (J) and an indicator of platelet contamination are shown. To illustrate the level of sample degradation in a time-dependent manner, the levels of hsa-miR-197-3p (K), hsa-miR-485-3p (L) and hsa-miR-130b-5p (M) are shown. Significant differences were identified using one-way ANOVA with a post hoc Dunnett’s test and are indicated as * p<0.05, ** p<0.01.