IMPLEMENTING CRYOPRESERVATION OF HEMATOPOIETIC PROGENITORS TO IMPROVE PRODUCT QUALITY AND INFUSION TOLERANCE

Introduction: Dimethyl sulfoxide (DMSO) is the most frequently used cryoprotective agent for freezing hematopoietic progenitors for transplantation. DMSO can cause adverse effects during cellular product infusion. In this setting, we reduced the DMSO concentration from 10% to 5% as a strategy to reduce toxicity. Methods: We retrospectively analyzed the characteristics of hematopoietic progenitor products and infusion tolerance in 240 adult patients who underwent autologous peripheral blood transplantation between January 2008 and February 2019. Patients were divided into two groups according to DMSO concentrations, 10% versus 5%. Results Post-thawing cell viability was signicantly higher in the 5% DMSO group (69.15% vs. 63.85%; p=0.028). In both groups, no statistically signicant differences were observed in the total content of CD34+×106/kg progenitor cells infused (DMSO 5% 2.98 vs. DMSO 10% 3.20, p=0.409), or graft recovery and transfusion needs. In all patients, the overall rate of adverse reactions was 7.5% (n=18); the rate was 4.6% (n=5) in the 5% DMSO group compared with 9.8% (n=13) in 10% DMSO (p=0.127). Severe adverse events were observed in the 10% DMSO group. Conclusion: Reducing the DMSO concentration from 10% to 5% is safe for the patient and product, improving viability and the absence of severe adverse infusion reactions.