Effect of trehalose on cryopreservation of pure peripheral blood stem cells.

Stem cells are an important tool for the study of hematopoiesis. Despite developments in cryopreservation, post-thaw cell death remains a considerable problem. Cryopreservation protocol should limit cell damage due to freezing and ensure the recovery of the functional cell characteristics after thawing. Thus, the use of cryoprotectants is essential. In particular, the efficacy of trehalose has been reported for clinical purposes in blood stem cells. The aim of the current study was to establish an efficient method for biological research based on the use of trehalose, to cryopreserve pure peripheral blood stem cells. The efficacy of trehalose was assessed in vitro and the cell viability was evaluated. The data indicate that trehalose improves cell survival after thawing compared with the standard freezing procedure. These findings could suggest the potential for future trehalose application for research purposes in cell cryopreservation.

Evaluation of biochemical parameters in platelet concentrates stored in glucose solution.

BACKGROUND: Therapeutic storage of platelet concentrate is a challenging problem for Transfusion Medicine, so that many studies have been carried out with the aim of improving the duration of storage of platelet concentrates. Little attention, however, has been given to the most appropriate biochemical methods for evaluating the quality of the stored platelet concentrates. MATERIAL AND METHODS: [corrected] Platelet concentrates (n=10) were saved under gentle stirring at 22 masculineC for a total period of 8 days. Glucose 0.5% (w/v) was added either at the beginning of storage (time 0) or on the fifth day of storage. One millilitre of each concentrate was withdrawn at time 0 and after 5, 6, 7 and 8 days of storage for microbiological culture, evaluation of pH, lactate dehydrogenase (LDH), mean platelet volume, platelet haematocrit and analysis of metabolites of energy pathways (high energy phosphate derivatives, nucleosides, oxypurines and antioxidants) by high performance liquid chromatography. RESULTS: The addition of glucose 0.5% on day 5 did not produce significant differences in metabolites of energy pathways with respect to control platelet concentrates, whereas when the glucose was added at the beginning of storage (time 0) there was a recovery of ATP, GTP and a decrease of energetic catabolism, demonstrating a beneficial effect on energy metabolism. The changes in LDH values did not parallel those of the metabolites: indeed, only on day 7 of storage did the platelet concentrates treated with glucose on day 5 have significantly lower levels of this enzyme than those found in the other concentrates. The improvements produced by addition of glucose at time 0 were confirmed by morphological analyses (mean platelet volume, platelet haematocrit), and the pH. CONCLUSIONS: The metabolic profile of glucose-enriched plasma concentrates on the fifth day of storage, and the different time course of increased LDH concentration, could represent valid parameters to interpret platelet vitality in the successive days of storage. These preliminary data also indicate that glucose might be a good additive for a new storage formulation.