Donor sex, age and ethnicity impact stored red blood cell antioxidant metabolism through mechanisms in part explained by glucose 6-phosphate dehydrogenase levels and activity

Red blood cell storage in the blood bank promotes the progressive accumulation of metabolic alterations that may ultimately impact the erythrocyte capacity to cope with oxidant stressors. However, the metabolic underpinnings of the capacity of RBCs to resist oxidant stress and the potential impact of donor biology on this phenotype are not known. Within the framework of the REDS-III RBC-Omics study, RBCs from 8,502 healthy blood donors were stored for 42 days and tested for their propensity to hemolyze following oxidant stress. A subset of extreme hemolyzers donated a second unit of blood, which was stored for 10, 23, and 42 days and profiled again for oxidative hemolysis and metabolomics (599 samples). Alterations of RBC energy and redox homeostasis were noted in donors with high oxidative hemolysis. RBCs from females, donors over 60 years old, donors of Asian/South Asian race-ethnicity, and RBCs stored in additive solution-3 were each independently characterized by improved antioxidant metabolism compared to, respectively, males, donors under 30 years old, Hispanic and African American race ethnicity donors, and RBCs stored in additive solution-1. Merging metabolomics data with results from an independent GWAS study on the same cohort, we identified metabolic markers of hemolysis and G6PD-deficiency, which were associated with extremes in oxidative hemolysis and dysregulation in NADPH and glutathione-dependent detoxification pathways of oxidized lipids. Donor sex, age, ethnicity, additive solution and G6PD status impact the metabolism of the stored erythrocyte and its susceptibility to hemolysis following oxidative insults

Towards microfluidic-based depletion of stiff and fragile human red cells that accumulate during blood storage

In this study, the effects of prolonged storage on several biophysical properties of red blood cells (RBCs) were investigated. Single cell deformability was used as an important criterion in determining subgroups of RBCs evolved during storage lesion. A deformability-based microfluidic cell sorting technology was applied, which demonstrates the ability to enrich and separate the less deformable subpopulations of stored blood. These less deformable RBC subpopulations were then associated with other important markers such as osmotic fragility indicating cell integrity as well as microparticle content. This work demonstrates a systematic methodology to both monitor and improve banked blood quality, thereby reducing risks related to blood transfusion.United States. Defense Advanced Research Projects Agency (N66001-11-1-4182

Additive effects of blood donor smoking and gamma irradiation on outcome measures of red blood cell transfusion

BACKGROUND: Recent publications have reported conflicting results regarding the role of blood donor tobacco use on hemoglobin levels in patients following red blood cell (RBC) transfusion. We examined associations and interactions between donor, component, and recipient factors to better understand the impact of donor smoking on transfusion outcomes. STUDY DESIGN AND METHODS: We linked blood donor and component manufacturing data, including self-reported cigarette smoking, with a cohort of patients transfused RBCs between 2013 and 2016. Using multivariable regression, we examined hemoglobin increments and subsequent transfusion requirements following single-unit RBC transfusion episodes, adjusting for donor, component, and recipient factors. RESULTS: We linked data on 4,038 transfusion recipients who received one or more single-unit RBC transfusions (n=5,086 units) to donor demographic and component manufacturing characteristics. Among RBC units from smokers (n=326), hemoglobin increments were reduced following transfusion of gamma irradiated units (0.76 g/dL; p=0.033) but not unirradiated units (1.04 g/dL; p=0.54) compared to those from non-smokers (1.01 g/dL; n=4,760). In parallel with changes in hemoglobin levels, donor smoking was associated with the receipt of additional RBC transfusions for irradiated (OR 2.49; p=0.01) but not unirradiated RBC units (OR 1.10; p=0.52). CONCLUSION: Donor smoking was associated with reduced hemoglobin increments and the need for additional transfusions in recipients of gamma irradiated RBC units. Additional research is needed to better understand interactions between donor, component, and recipient factors on efficacy measures of RBC transfusion

Blood donor obesity is associated with changes in red blood cell metabolism and susceptibility to hemolysis in cold storage and in response to osmotic and oxidative stress

BackgroundObesity is a global pandemic characterized by multiple comorbidities, including cardiovascular and metabolic diseases. The aim of this study was to define the associations between blood donor body mass index (BMI) and RBC measurements of metabolic stress and hemolysis.Study design and methodsThe associations between donor BMI (<25 kg/m2 , normal weight; 25-29.9 kg/m2 , overweight; and ≥30 kg/m2 , obese) and hemolysis (storage, osmotic, and oxidative; n = 18 donors) or posttransfusion recovery (n = 14 donors) in immunodeficient mice were determined in stored leukocyte-reduced RBC units. Further evaluations were conducted using the National Heart, Lung, and Blood Institute RBC-Omics blood donor databases of hemolysis (n = 13 317) and metabolomics (n = 203).ResultsEvaluations in 18 donors revealed that BMI was significantly (P < 0.05) and positively associated with storage and osmotic hemolysis. A BMI of 30 kg/m2 or greater was also associated with lower posttransfusion recovery in mice 10 minutes after transfusion (P = 0.026). Multivariable linear regression analyses in RBC-Omics revealed that BMI was a significant modifier for all hemolysis measurements, explaining 4.5%, 4.2%, and 0.2% of the variance in osmotic, oxidative, and storage hemolysis, respectively. In this cohort, obesity was positively associated (P < 0.001) with plasma ferritin (inflammation marker). Metabolomic analyses on RBCs from obese donors (44.1 ± 5.1 kg/m2 ) had altered membrane lipid composition, dysregulation of antioxidant pathways (eg, increased oxidized lipids, methionine sulfoxide, and xanthine), and dysregulation of nitric oxide metabolism, as compared to RBCs from nonobese (20.5 ± 1.0 kg/m2 ) donors.ConclusionsObesity is associated with significant changes in RBC metabolism and increased susceptibility to hemolysis under routine storage of RBC units. The impact on transfusion efficacy warrants further evaluation