Heterogeneity of blood processing and storage additives in different centers impacts stored red blood cell metabolism as much as storage time: lessons from REDS‐III—Omics

Abstract

Background Biological and technical variability has been increasingly appreciated as a key factor impacting red blood cell (RBC) storability and, potentially, transfusion outcomes. Here we performed metabolomics analyses to investigate the impact of factors other than storage duration on the metabolic phenotypes of stored RBC in a multi-center study. Study design and Methods Within the framework of the REDS-III RBC-Omics study, 13,403 donors were enrolled from four blood centers across the United States and tested for the propensity of their RBCs to hemolyze after 42 days of storage. Extreme hemolyzers were recalled and donated a second unit of blood. Units were stored for 10, 23 and 42 days prior to sample acquisition for metabolomics analyses. Results Unsupervised analyses of metabolomics data from 599 selected samples revealed a strong impact (14.2% of variance) of storage duration on metabolic phenotypes of RBCs. The blood center collecting and processing the units explained an additional 12.2% of the total variance, a difference primarily attributable to the storage additive (AS-1 vs AS-3) used in the different hubs. Samples stored in mannitol-free/citrate-loaded AS-3 were characterized by elevated levels of high-energy compounds, improved glycolysis and glutathione homeostasis. Increased methionine metabolism and activation of the trans-sulfuration pathway was noted in samples processed in the center using AS-1. Conclusion Blood processing impacts the metabolic heterogeneity of stored RBCs from the largest multi-center metabolomics study in transfusion medicine to date. Studies are needed to understand if these metabolic differences influenced by processing/storage strategies impact the effectiveness of transfusions clinically.

Piloting and implementation of quality assessment and quality control procedures in RBC‐Omics: a large multi‐center study of red blood cell hemolysis during storage

“…Results showed that metabolites have varying sensitivity to freezing methods, which must be accounted for if future metabolomics analysis is planned using the screening phase samples which were initially frozen at –80°C rather than snap frozen in liquid nitrogen, followed by freezing in mechanical freezers at –80°C. Metabolomics analysis performed on recall samples demonstrated excellent sample quality …”

Chronological storage age and metabolic age of stored red blood cells: are they the same?

“…To graphically represent this conclusion, we reelaborated results from a recent report from the REDS‐III RBC‐Omics study (Fig. ) . In this study, approximately 14,000 healthy volunteer donors were enrolled to donate a unit of whole blood, which was processed into leukoreduced RBC components that were stored for 42 days.…”

“…Heterogeneity of storage‐induced changes in key metabolic markers of redox and energy metabolism in RBCs from the REDS‐III Omics study (elaboration of data from D'Alessandro et al) . Red and blue lines indicate the top 20 highest and lowest donors with respect to GSH levels on Storage Days 10, 23, and 42, a variable that should be representative of RBC antioxidant capacity (center panel) and thus the propensity of RBCs to store well or poorly (good storer vs. poor storer).…”

Translating red cell “omics” into new perspectives in transfusion medicine: mining the gems in the data mountains

“…The RBC‐Omics investigators have now published seven significant and interrelated papers in Transfusion . These can be topically arranged as follows: (1) design of the REDS‐III RBC‐Omics program and performance of pilot and method optimization studies, and execution of a quality assurance program; (2) in vitro hemolysis testing of donated RBCs from recalled RBC‐Omics donors (focusing on methodology, reproducibility, and changes in hemolysis measures through storage of RBC components from the recalled donors); (3) in vitro hemolysis testing of RBCs relative to previous donation intensity, including donations by so‐called “super donors”; (4) general metabolomics studies of donated RBCs throughout the storage interval; (5) intermediary metabolism of methionine and trans‐sulfuration in stored RBCs; and (6) design of the methodology for GWAS of RBC donors . Although the last paper focused entirely on methodology, it is anticipated that some GWAS results using these methods will be available soon…”

“…The efforts of D'Alessandro et al focused on sophisticated metabolomics analyses of recall samples obtained from the “extreme hemolyzers” identified by the in vitro hemolysis assays described above . In this case, entire units were obtained for experimental study and samples were obtained at three time points during storage.…”