Buffy coat-derived platelets cryopreserved using a new method: Results from in vitro studies

Cryopreservation for the long-term storage of platelets (PLTs) is a useful method to overcome the limits of platelet shortage. This is an in vitro prospective study to evaluate the count, viability, and function of buffy coat-derived pooled platelet concentrates (BC-PLTs), treated with dimethyl sulphoxide (DMSO) and cryopreserved (CRY BC-PLTs) at ?80?°C with a modified Valeri method. PLTs were stored in 6% DMSO with a patented kit. Overall, 49 BC-PLTs from 245 healthy volunteer donors were prepared, cryopreserved, and analysed before and after 3, 6, and 9?months of storage. In flow cytometry, a statistically significant reduction in CD 42b (92.7?±?4.29% at T0 vs. 23.6?±?27.5% at T3, 16.38?±?12.54% at T6, and 17.3?±?9.6% at T9) and PAC-1 (1.9?±?1.34% at T0 vs. 0.62?±?0.4% at T3, 0.63?±?0.83% at T6, and 0.49?±?0.48% at T9) was observed after storage. CRY BC-PLTs showed a good and stable endogenous thrombin generation potential (nM min): 529.25?±?98.64 at T0 vs. 533.04?±?103.15 at T9 months. CRY BC-PLTs showed a good viability in vitro, according to currently accepted criteria for cryopreserved PLTs.