Annexin V Release and Transmembrane Mitochondrial Potential during Storage of Apheresis-Derived Platelets Treated for...

BACKGROUND: In vitro function of stored platelet (PLT) con-centrates was analyzed after applying two different techniques of pathogen reduction technology (PRT) treatment, which could increase cellular injury during processing and storage. METHODS: Nine triple-dose PLT apheresis donations were split into 27 single units designated to riboflavin-UVB (M) or psoralen-UVA (I) treatment or remained untreated (C). Throughout 8 days of storage, samples were analyzed for annexin V release, the mitochondrial transmembrane potential (Deltapsi) and some classical markers of PLT quality (pH, LDH release, hypotonic shock response (HSR)). RESULTS: PLT count and LDH release of all units maintained initial ranges. All units exhibited a decrease in pH and HSR and an increase in annexin V release and Deltapsi disruption. Notably, throughout the entire storage period, annexin V release re-mained lowest in M units. Throughout 7 days of storage, M units remained comparable to C units (p > 0.05), whereas inferior values were observed with I units. Here, differences to C units reached significance by day 1 (pH: p < 0.0001), day 5 (annexin V release: p < 0.014), and day 7 (HSR, Deltapsi: p