Effects of pre‐freeze pathogen reduction with riboflavin and UV light on red cells stored post‐thaw in AS‐3 additive solution.

Background: Pathogen reduction technology (PRT) may improve the safety of RBCs for transfusion. As the Czech Republic considers PRT, we asked what effects riboflavin and UV light PRT pre‐freezing has on the post‐thaw recovery and properties of cryopreserved RBCs (CRBCs) after deglycerolization and liquid storage. Study Design and Methods: 24 Group O whole blood (WB) units were leukoreduced and then treated with riboflavin and UV light PRT (Mirasol, Terumo BCT, USA) before cryopreservation (T‐CRBC); 20 similarly‐collected units were untreated controls (C‐CRBC). Units were processed to RBCs and then cryopreserved with 40% glycerol (wt/vol), frozen at −80°C, stored >118 days, reconstituted as deglycerolized RBC units in AS‐3, and stored at 4 ± 2°C for 21 days. One treated unit sustained massive hemolysis during the post‐thaw wash process and was removed from data analysis. The remaining units were assessed pre‐PRT, post‐PRT, and post‐thaw‐wash on days 0, 7, 14, and 21 for hematocrit, volume, hemoglobin per transfusion unit, pH, % hemolysis, hemoglobin in the supernatant, potassium, phosphorus, NH3, osmolality, ATP, and 2,3‐diphosphoglycerate. Results: PRT with leukoreduction caused a 5% loss of RBC followed by a 24% freeze–thaw‐wash related loss for a total 28% loss but treated units contained an average of 45 g of hemoglobin, meeting European Union guidelines for CRBC. T‐CRBCs displayed higher post‐wash hemolysis, potassium, and ammonia concentrations, and lower ATP at the end of storage. Conclusions: Cryopreserved RBCs from Riboflavin and UV light‐treated WB meet the criteria for clinical use for 7 days after thawing and provide additional protection against infectious threats. [ABSTRACT FROM AUTHOR]