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.

Cryopreservation of apheresis platelets treated with riboflavin and UV light.

BACKGROUND: Pathogen reduction technology (PRT) is increasingly used in the preparation of platelets for therapeutic transfusion. As the Czech Republic considers PRT, we asked what effects PRT may have on the recovery and function of platelets after cryopreservation (CP), which we use in both military and civilian blood settings. STUDY DESIGN AND METHODS: 16 Group O apheresis platelets units were treated with PRT (Mirasol, Terumo BCT, USA) before freezing; 15 similarly collected units were frozen without PRT as controls. All units were processed with 5-6% DMSO, frozen at - 80 °C, stored > 14 days, and reconstituted in thawed AB plasma. After reconstitution, all units were assessed for: platelet count, mean platelet volume (MPV), platelet recovery, thromboelastography, thrombin generation time, endogenous thrombin potential (ETP), glucose, lactate, pH, pO2, pCO2, HCO3, CD41, CD42b, CD62, Annexin V, CCL5, CD62P, and aggregates > 2 mm and selected units for Kunicki score. RESULTS: PRT treated platelet units had lower platelet number (247 vs 278 ×109/U), reduced thromboelastographic MA (38 vs 62 mm) and demonstrated aggregates compared to untreated platelets. Plasma coagulation functions were largely unchanged. CONCLUSIONS: Samples from PRT units showed reduced platelet number, reduced function greater than the reduced number would cause, and aggregates. While the platelet numbers are sufficient to meet the European standard, marked platelets activation with weak clot strength suggest reduced effectiveness.

Optimizing the supply of whole blood-derived bioproducts through the combined implementation of cryopreservation and pathogen reduction technologies and practices: An overview.

The essential historical knowledge and expertise developed over the past 5-6 decades on the safety / efficacy of conventional blood components therapy by blood transfusion establishments have guided the development of validated methods which have ensure optimal safety margins for frozen blood and its bioproducts with or even without pathogen reduction. Newer generations of pathogen reduced frozen red blood cell, plasma and platelet products and the standardised and safer pooling of human platelet lysate are now become available for potential clinical use. These types of whole blood-derived bioproducts not only reduce the risk of transmission of range of pathogenic blood-borne pathogen. As cryopreservation can be combined with PRT without significantly compromising in vitro quality characteristics or physiological capabilities, it allows us to maximize the available inventory of these blood products in both civil and military trauma settings. The main objective of this overview is to update readers and scientific / medical communities of the various building blocks needed to optimally grantee the pathogen safety of whole blood-derived bioproducts, with minimal untoward events to the recipients. While this is an emerging area, we are seeing the numerous potential opportunities that cryopreservation and pathogen inactivation can have on the transfused patient outcomes. This manuscript is informed by recent publications on this topic.

The use of cryopreserved platelets in the treatment of polytraumatic patients and patients with massive bleeding.

BACKGROUND: The short shelf-life of fresh platelets limits their efficient inventory management and availability during a massive transfusion protocol. Risk of insufficient availability can be mitigated by building an inventory of cryopreserved platelets (CPs). METHODS: A comparative study of fresh apheresis platelets (FAPs) and CPs was performed. Type-O CPs were processed with DMSO frozen at -80°C and reconstituted in thawed AB plasma. All patients enrolled in the study had the following parameters evaluated on admission: vital signs (body temperature, heart rate, mean arterial pressure), blood count, prothrombin time, activated partial thromboplastin time, fibrinogen level, and, in trauma patients, international severity score. Several outcomes were evaluated: 30-day survival, adverse events, quantity of administered blood products, fibrinogen concentrate and thromboxane (TXA), and laboratory parameters after transfusion (blood count, prothrombin time, activated partial thromboplastin time, fibrinogen level). RESULTS: Twenty-five (25) patients in the study group received transfusions totaling 81 units of CPs. Twenty-one (21) patients in the control group received a total of 67 units of FAPs. There were no significant differences in patient characteristics (p > 0.05) between groups. Both groups were comparable in clinical outcomes (30-day survival, administered blood products, fibrinogen concentrate, TXA, and adverse events). Among posttransfusion laboratory parameters, platelet count was higher in the group transfused with FAPs (97.0 ×109 /L) than in the group transfused with CPs (41.5 ×109 /L), p = 0.02025. Other parameters were comparable in both groups. CONCLUSION: The study suggests that CPs are tolerable and a feasible alternative to FAPs. However, larger randomized studies are needed to draw definitive conclusions.