In Vitro Characterization and Metabolomic Analysis of Cold-Stored Platelets

Platelet concentrates are currently stored at room temperature (RP) under constant agitation for up to 5-7 days depending on national regulations. However, platelet quality deteriorates during storage and room-temperature storage also increases the risk of bacterial growth. Previous studies have shown that cold-stored platelets (CPs) have higher hemostatic functions and can be stored for up to 3 weeks. While these studies have compared the metabolic phenotypes of CPs and RPs, they have neither compared the impact of storage temperature and cold agitation (CPAs) on platelet function nor identified metabolic correlates to such parameters. In vitro analysis showed that CPAs and CPs had reduced count, faster CD62P expression, and increased lactadherin binding. Furthermore, CPAs and CPs had higher maximal aggregation and a reduced aggregation lag phase compared to RPs. Metabolomic analysis revealed that CPAs and CPs exhibited lower oxidative stress shown by preserved glutathione and pentose phosphate pools. CPAs and CPs also had reduced markers of beta-oxidation and amino acid catabolism, demonstrating reduced needs for energy. Agitation did not significantly impact in vitro function or metabolomic parameters of cold-stored platelets. Correlation of in vitro and metabolomic results highlighted important metabolites that may contribute to stored platelet functions. Raw data are publicly available through Metabolomics Workbench with the study identifier ST001644.