Drawing and storing blood using a 3D printed bottle cap and a disinfected 500 mL drinking bottle: A proof-of-concept study.

BACKGROUND: Today, with wars raging in Ukraine and the Middle East, the demand for blood is high. Despite this, few companies produce the necessary equipment to draw, store, and transfuse whole blood. This study evaluated the safety and performance of a 3D printed bottle cap in conjunction with a water bottle and some available consumables to draw and store fresh whole blood. STUDY DESIGN AND METHODS: Bags of saline, and freshly donated whole blood, was transferred to the water bottle through a 3D printed bottle cap and stored for 72 h. An identical setup, transferring saline to a Terumo blood collection bag was used as control. Performance and safety were evaluated by calculating infusion rate and observing for backflow, respectively. The blood was also tested for hemolysis and bacterial growth at four sampling points. RESULTS: The cap-and-bottle setup was faster than control in terms of flow rate when transferring saline (1.53 vs. 1.81 mL/s, p < .001), and non-inferior to saline control when transfusing blood (1.53 vs. 1.49 mL/s, p = .641). We did not observe any risks of causing the donor iatrogenic harm, and there was no evidence of increased hemolysis. However, there were traces of bacterial contamination in three of six bottles. CONCLUSION: This study indicates that drawing blood is both feasible and safe, utilizing a 3D printed cap and bottle setup. Flow rate was faster than control, and mechanical properties of the blood were not affected. We were unable to determine the source of bacterial contamination in the blood.

A 3-step method for preparing cryopreserved samples of apheresis products for post-thaw analysis yields a higher percentage of viable cells.

BACKGROUND: Standard flow cytometry protocols for CD34+ cell enumeration designed for fresh samples are not appropriate for cryopreserved products. Special protocols have been developed to remove the cryoprotectant by quickly washing a freshly thawed sample. Exposing cells to a large volume of hypotonic solution and subsequent washing process was hypothesized to cause lab-induced cell death. Moreover, standard gating strategies must be altered to avoid reporting falsely high viabilities. STUDY DESIGN AND METHODS: We developed a novel method whereby thawed samples were diluted step-wise to 1:2 by 3 additions of 1/3 sample volume using 1% Human Albumin in Dextran 40 (10% Low Molecular Weight Dextran in 0.9% NaCl) separated by 5 min between each addition. An additional 1:10 dilution was required to obtain a desired cell concentration for flow cytometry testing resulting in a 1:20 dilution. RESULTS: Twenty samples were tested simultaneously in a method comparison; the new method demonstrated significant increases in mean cell viabilities for white blood cells, hematopoietic progenitor cells, and T cells as well as reduced standard deviations for each parameter. DISCUSSION: Slow, step-wise dilutions of freshly thawed samples of cryopreserved apheresis products to 1:20 yielded higher and more precise viability measurements compared to quickly washing samples to remove DMSO.

A perspective on exogenous redox regulation mediated by transfused RBCs subject to the storage lesion.

Granted with a potent ability to interact with and tolerate oxidative stressors, RBCs scavenge most reactive oxygen and nitrogen species (RONS) generated in circulation. This essential non-canonical function, however, renders RBCs susceptible to damage when vascular RONS are generated in excess, making vascular redox imbalance a common etiology of anemia, and thus a common indication for transfusion. This accentuates the relevance of impairments in redox metabolism during hypothermic storage, as the exposure to chronic oxidative stressors upon transfusion could be exceedingly deleterious to stored RBCs. Herein, we review the prominent mechanisms of the hypothermic storage lesion that alter the ability of RBCs to scavenge exogenous RONS as well as the associated clinical relevance.

Evaluation of platelets componentized with the Reveos Automated Blood Processing System and stored for 7 days at room temperature in a non-Di(2-ethylhexyl) phthalate (DEHP) platelet pooling set.

BACKGROUND: Platelet concentrates (PCs) used for transfusion can be produced by apheresis or derived from whole blood (WB). The Reveos device is the first US Food and Drug Administration-approved automated blood processing system that can produce PCs. In this work, we evaluated the quality and function of Reveos-collected PCs stored for 7 days at room temperature. STUDY DESIGN AND METHODS: WB was collected from healthy donors and componentized on the day of collection (Fresh) or after an overnight hold (Overnight). PCs were produced (n = 7 Fresh; n = 6 Overnight), stored at room temperature in plasma, and evaluated on days 1 and 7 for quality metrics, platelet activation, clot formation, and aggregation response. RESULTS: Platelet count was comparable between Fresh and Overnight PCs. A drop in pH was reported in Fresh day 7 PCs (p < .001, vs. day 1) but not in Overnight. Overnight units displayed the lowest levels of P-selectin expression (p = .0008, vs. day 7 Fresh). Reduced clot strength and increased lysis were observed in both Fresh and Overnight units on day 7 (vs. day 1). Overnight-hold PCs resulted in the highest clot strength on day 7 (p = .0084, vs. Fresh). No differences in aggregation were reported between groups. CONCLUSION: Reveos-processed PCs produced from overnight-hold WB performed better in hemostatic function assays and displayed reduced activation compared to fresh WB-derived PCs, although both PC groups maintained platelet quality throughout storage. Utilization of overnight WB for PC preparation with Reveos holds promise as an alternative method of producing platelets for transfusion purposes.

Platelet dysfunction reversal with cold-stored vs room temperature-stored platelet transfusions.

ABSTRACT: Platelets are stored at room temperature for 5 to 7 days (room temperature-stored platelets [RSPs]). Because of frequent and severe shortages, the US Food and Drug Administration recently approved up to 14-day cold-stored platelets (CSPs) in plasma. However, the posttransfusion function of CSPs is unknown and it is unclear which donors are best suited to provide either RSPs or CSPs. In this study, we sought to evaluate the posttransfusion platelet function and its predictors for platelets stored for the maximum approved storage times (7-day RSPs and 14-day CSPs) in healthy volunteers on acetylsalicylic acid (ASA). We conducted a randomized crossover study in 10 healthy humans. Individuals donated 1 platelet unit, stored at either 22°C or 4°C based on randomization. Before transfusion, participants ingested ASA to inhibit endogenous platelets. Transfusion recipients were tested for platelet function and lipid mediators. Platelet units were tested for lipid mediators only. A second round of transfusion with the alternative product was followed by an identical testing sequence. RSPs reversed platelet inhibition significantly better in αIIbß3 integrin activation-dependent assays. In contrast, CSPs in recipients led to significantly more thrombin generation, which was independent of platelet microparticles. Lysophosphatidylcholine-O species levels predicted the procoagulant capacity of CSPs. In contrast, polyunsaturated fatty acid concentrations predicted the aggregation response of RSPs. In summary, we provide, to our knowledge, the first efficacy data of extended-stored CSPs in plasma. Our results suggest that identifying ideal RSP and CSP donors is possible, and pave the way for larger studies in the future. This trial is registered at www.ClinicalTrials.gov as #NCT0511102.

Comparable bacterial growth in platelet concentrates suspended in plasma and platelet additive solution and improved detection of bacterial contamination using a new generation automated culture system.

BACKGROUND: Microbial screening of platelet concentrates (PC) with automated culture methods is widely implemented to reduce septic transfusion reactions. Herein, detection of bacterial contamination in PC was compared between units prepared in plasma and a mix of plasma and platelet additive solution (PAS) and between the BACT/ALERT 3D and next generation BACT/ALERT VIRTUO systems. STUDY DESIGN/METHODS: Double apheresis units were split into single units, diluted in either PAS (PAS-PC) or plasma (plasma-PC), and tested for in vitro quality and sterility prior to spiking with ~30 CFU/unit of Staphylococcus epidermidis, Staphylococcus aureus, Serratia marcescens, and Klebsiella pneumoniae or ~10 CFU/mL of Cutibacterium acnes. Spiked PC were sampled for BACT/ALERT testing (36 and 48 h post-spiking) and colony counts (24, 36, and 48 h post-spiking). Times to detection (TtoD) and bacterial loads were compared between PC products and BACT/ALERT systems (N = 3). RESULTS: Bacterial growth was similar in plasma-PC and PAS-PC. No significant differences in TtoD were observed between plasma-PC and PAS-PC at the 36-h sampling time except for S. epidermidis which grew faster in plasma-PC and C. acnes which was detected earlier in PAS-PC (p < .05). Detection of facultative bacteria was 1.3-2.2 h sooner in VIRTUO compared with 3D (p < .05) while TtoD for C. acnes was not significantly different between the two systems. DISCUSSION: Comparable bacterial detection was observed in plasma-PC and PAS-PC with PC sampling performed at 36-h post blood collection. PC sampling at ≤36 h could result in faster detection of facultative pathogenic organisms with the VIRTUO system and improved PC safety.

Evaluating the effects of hypoxic storage on platelet function and health using a novel storage system.

BACKGROUND: Thousands of units of whole blood (WB) and blood components are transfused daily to treat trauma patients. Improved methods for blood storage are critical to support trauma-related care. The Hemanext ONE® system offers a unique method for hypoxic storage of WB, with successfully demonstrated storage of clinically viable RBCs. This work evaluated the system for the storage of WB, focusing on platelet health and function. STUDY DESIGN AND METHODS: WB was collected from healthy donors and processed through the Hemanext ONE® system. Hemoglobin oxygen saturation (HbSO2) levels of WB were depleted to 10%, 20%, or 30% of total HbSO2 and then stored in PVC bags sealed in oxygen-impermeable bags (except for normoxic control) with samples collected on days 1, 7, and 14 post-processing. Flow cytometry assessed the activation and apoptosis of platelets. Clot dynamics were assessed based on aggregometry and thromboelastography assays, as well as thrombin generation using a calibrated-automated thrombogram method. RESULTS: Hypoxic storage conditions were maintained throughout the storage period. Hypoxia triggered increased lactate production, but pH changes were negligible compared to normoxic control. Storage at 10% HbSO2 had a significant impact on platelet function, resulting in increased activation and reduced clot formation and aggregation. These effects were less significant at 20% and 30% HbSO2. DISCUSSION: This study indicates that platelets are sensitive to hypoxic storage and suffer significant metabolic and functional deterioration when stored at or below 10% HbSO2.

Red Blood Cell Storage with Xenon: Safe or Disruption?

Xenon, an inert gas commonly used in medicine, has been considered as a potential option for prolonged preservation of donor packed red blood cells (pRBCs) under hypoxic conditions. This study aimed to investigate how xenon affects erythrocyte parameters under prolonged storage. In vitro model experiments were performed using two methods to create hypoxic conditions. In the first method, xenon was introduced into bags of pRBCs which were then stored for 42 days, while in the second method, xenon was added to samples in glass tubes. The results of our experiment showed that the presence of xenon resulted in notable alterations in erythrocyte morphology, similar to those observed under standard storage conditions. For pRBC bags, hemolysis during storage with xenon exceeded the acceptable limit by a factor of six, whereas the closed-glass-tube experiment showed minimal hemolysis in samples exposed to xenon. Notably, the production of deoxyhemoglobin was specific to xenon exposure in both cell suspension and hemolysate. However, this study did not provide evidence for the purported protective properties of xenon.

Understanding interactions of plasticisers with a phospholipid monolayer.

The use of DEHP (diethylhexyl phthalate) is now banned for most applications in Europe; the exception is for blood bags, where its toxicity is overshadowed by its ability to extend the storage life of red blood cells. Another plasticiser, BTHC (butanoyl trihexyl citrate), is used in paediatric blood bags but does not stabilise blood cells as effectively. Interactions between plasticisers and lipids are investigated with a phospholipid, DMPC, to understand the increased stability of blood cells in the presence of DEHP as well as bioaccumulation and identify differences with BTHC. Mixed monolayers of DMPC and DEHP or BTHC were studied on Langmuir troughs where surface pressure/area isotherms can be measured. Neutron reflection measurements were made to determine the composition and structure of these mixed layers. A large amount of plasticiser can be incorporated into a DMPC monolayer but once an upper limit is reached, plasticiser is selectively removed from the interface at high surface pressures. The upper limit is found to occur between 40-60 mol% for DEHP and 20-40 mol% for BTHC. The areas per molecule are also different with DEHP being in the range of 50-100 Å2 and BTHC being 65-120 Å2. Results indicate that BTHC does not fit as well as DEHP in DMPC monolayers which could help explain the differences observed with regards to the stability of blood cells.

Preservation of recipient plasma sphingosine-1-phosphate levels reduces transfusion-related acute lung injury.

Cold-stored (CS) platelets are once again being reintroduced for clinical use. Transfused CS platelets offer benefits over room temperature-stored (RTS) platelets such as increased hemostatic effects and prolongation of shelf-life. Despite these advantages little is known about their association with transfusion-related acute lung injury (TRALI). TRALI is associated with prolonged storage of RTS platelets and has a mortality of >15%. Determining the safety of CS platelets is important considering their proposed use in TRALI-vulnerable populations with inflammation such as surgical patients or patients with trauma. Donor platelet-derived ceramide causes TRALI, whereas donor platelet sphingosine-1-phosphate (S1P) is barrier protective. Females have higher plasma levels of S1P than males. Cold temperatures increase S1P levels in cells. Therefore, we hypothesized that female (donors or recipients) and/or CS platelets would decrease TRALI. To test this, we compared how male and female donor and recipient allogeneic platelet transfusions of CS (4°C) versus RTS (23°C) platelets stored for 5 days influence murine TRALI. Transfusion of CS platelets significantly reduced recipient lung tissue wet-to-dry ratios, bronchoalveolar lavage total protein, lung tissue myeloperoxidase enzyme activity, histological lung injury scores, and increased plasma sphingosine-1-phosphate (S1P) levels compared with RTS platelet transfusions. Female as opposed to male recipients had less TRALI and higher plasma S1P levels. Female donor mouse platelets had higher S1P levels than males. Mouse and human CS platelets had increased S1P levels compared with RTS platelets. Higher recipient plasma S1P levels appear protective considering females, and males receiving platelets from females or male CS platelets had less TRALI.NEW & NOTEWORTHY Transfusion-related acute lung injury (TRALI) though relatively rare represents a severe lung injury. The sphingolipid sphingosine-1-phosphate (S1P) regulates the severity of platelet-mediated TRALI. Female platelet transfusion recipient plasmas or stored platelets from female donors have higher S1P levels than males, which reduces TRALI. Cold storage of murine platelets preserves platelet-S1P, which reduces TRALI in platelet-transfused recipients.

Performance of far forward iceless blood storage containers in controlled cold environments.

BACKGROUND: The Golden Hour Box (GHB), an iceless blood container designed for transfusion closest to the point of injury, is used by military medical teams in remote damage control resuscitation. While its performance is well-established in hot environments, it remains underexplored in cold conditions, a significant consideration in emerging global conflict zones. STUDY DESIGN AND METHODS: Four GHBs were preconditioned at +4°C or +18°C for 8 h and subsequently exposed to controlled laboratory simulated temperatures of -5, -15, and -25°C for 100 h. The study focused on their capability to maintain an internal temperature between +2 and +6°C, the recommended range for red blood cells unit storage and transport, using calibrated sensors for precise monitoring. RESULTS: When exposed to negative Celsius temperatures, GHBs showed varied performance depending on preconditioning temperatures. When preconditioned at +4°C, GHBs maintained an internal temperature within the target range (+2 to +6°C) for 100 h at -5°C, 52 ± 1 h at -15°C, and 29 ± 4 h at -25°C. In contrast, the internal temperature of GHBs preconditioned at +18°C exceeded this range in less than 30 min, then dropped below 2°C more rapidly than those preconditioned at +4°C, occurring within 20 ± 2 h at -15 and 13 ± 1 h at -25°C. CONCLUSION: The GHB, when properly preconditioned, effectively maintains internal temperatures suitable for blood product transport in extreme cold. Future research, including analyses of blood performances, is still needed to validate these results in more realistic operational conditions for use in cold environments.

Impact of production methods and storage conditions on extracellular vesicles in packed red blood cells and platelet concentrates.

The use of blood and blood products can be life-saving, but there are also certain risks associated with their administration and use. Packed red blood cells (pRBCs) and platelet concentrates are the most commonly used blood products in transfusion medicine to treat anemia or acute and chronic bleeding disorders, respectively. During the production and storage of blood products, red blood cells and platelets release extracellular vesicles (EVs) as a result of the storage lesion, which may affect product quality. EVs are subcellular structures enclosed by a lipid bilayer and originate from the endosomal system or from the plasma membrane. They play a pivotal role in intercellular communication and are emerging as important regulators of inflammation and coagulation. Their cargo and their functional characteristics depend on the cell type from which they originate, as well as on their microenvironment, influencing their capacity to promote coagulation and inflammatory responses. Hence, the potential involvement of EVs in transfusion-related adverse events is increasingly recognized and studied. Here, we review the knowledge regarding the effect of production and storage conditions of pRBCs and platelet concentrates on the release of EVs. In this context, the mode of processing and anticoagulation, the influence of additive solutions and leukoreduction, as well as the storage duration will be addressed, and we discuss potential implications of EVs for the clinical outcome of transfusion.

A tight interplay between platelet activation and mitochondrial DNA release promotes platelet storage lesion in platelet concentrates.

BACKGROUND AND OBJECTIVES: Platelet storage lesion (PSL) adversely affects the quality of platelet concentrates (PCs). Platelets are prone to activation during storage. Moreover, elevated free mitochondrial DNA (mtDNA) levels in PCs are associated with a higher risk of adverse transfusion reactions. Therefore, we aimed to evaluate the correlation between platelet activation markers and mtDNA release during PC storage. MATERIALS AND METHODS: Six PCs prepared by the platelet-rich plasma method were assessed for free mtDNA copy number using quantitative real-time PCR and CD62P (P-selectin) expression by flow cytometry on days 0 (PC collection day), 3, 5 and 7 of storage. Lactate dehydrogenase (LDH) activity, pH, platelet count, mean platelet volume (MPV) and platelet distribution width (PDW) were measured as well. The correlation between free mtDNA and other PSL parameters, and the correlation between all parameters, was determined. RESULTS: Significant increases in free mtDNA, MPV and PDW, and a significant decrease in platelet count and pH were observed. CD62P expression and LDH activity elevated significantly, particularly on storage days 5-7 and 0-3, respectively. Moreover, a moderate positive correlation (r = 0.61) was observed between free mtDNA and CD62P expression. The r values between free mtDNA and LDH, pH, platelet count, MPV and PDW were 0.81, -0.72, -0.49, 0.81 and 0.77, respectively. CONCLUSION: The interplay between platelet activation and mtDNA release in promoting PSL in PCs may serve as a promising target for future research on applying additive solutions and evaluating the quality of PCs to improve transfusion and clinical outcomes.

Red cell concentrates from teen male donors contain poor-quality biologically older cells.

BACKGROUND AND OBJECTIVES: Donor factors influence the quality characteristics of red cell concentrates (RCCs) and the lesions that develop in these heterogeneous blood products during hypothermic storage. Teen male donors' RCCs contain elevated levels of biologically old red blood cells (RBCs). The aim of this study was to interrogate the quality of units of different donor ages and sexes to unravel the complex interplay between donor characteristics, long-term cold storage and, for the first time, RBC biological age. MATERIALS AND METHODS: RCCs from teen males, teen females, senior males and senior females were density-separated into less-dense/young (Y-RBCs) and dense/old RBCs (O-RBCs) throughout hypothermic storage for testing. The unseparated and density-separated cells were tested for haematological parameters, stress (oxidative and osmotic) haemolysis and oxygen affinity (p50). RESULTS: The O-RBCs obtained from teen donor samples, particularly males, had smaller mean corpuscular volumes and higher mean corpuscular haemoglobin concentrations. While biological age did not significantly affect oxygen affinity, biologically aged O-RBCs from stored RCCs exhibited increased oxidative haemolysis and decreased osmotic fragility, with teenage male RCCs exhibiting the highest propensity to haemolyse. CONCLUSION: Previously, donor age and sex were shown to have an impact on the biological age distribution of RBCs within RCCs. Herein, we demonstrated that RBC biological age, particularly O-RBCs, which are found more prevalently in male teens, to be a driving factor of several aspects of poor blood product quality. This study emphasizes that donor factors should continue to be considered for their potential impacts on transfusion outcomes.

Downscaling platelet cryopreservation: Are platelets frozen in tubes comparable to standard cryopreserved platelets?

BACKGROUND: Platelet cryopreservation extends the shelf-life to at least 2 years. However, platelets are altered during the freeze/thaw process. Downscaling platelet cryopreservation by freezing in tubes would enable rapid screening of novel strategies to improve the quality of cryopreserved platelets (CPPs). The aim of this study was to characterize the effect of freezing conditions on the in vitro phenotype and function of platelets frozen in a low volume compared to standard CPPs. METHODS: Platelets were prepared for cryopreservation using 5%-6% DMSO and processed using standard protocols or aliquoted into 2 mL tubes. Platelets were hyperconcentrated to 25 mL (standard CPPs) or 200 µL (tubes) before freezing at -80°C (n = 8). Six insulators/controlled rate freezing containers were used to vary the freezing rate of platelets in tubes. Platelets were thawed, resuspended in plasma, and then assessed by flow cytometry and thromboelastography. RESULTS: The use of different insulators for tubes changed the freezing rate of platelets compared to platelets frozen using the standard protocol (p < .001). However, this had no impact on the recovery of the platelets (p = .87) or the proportion of platelets expressing GPIbα (p = .46) or GPVI (p = .07), which remained similar between groups. A lower proportion of platelets frozen in tubes externalized phosphatidylserine compared to standard CPPs (p < .001). The clot-forming ability (thromboelastography) of platelets was similar between groups (p > .05). CONCLUSION: Freezing platelets in tubes modified the freezing rate and altered some platelet characteristics. However, the functional characteristics remained comparable, demonstrating the feasibility of downscaling platelet cryopreservation for high-throughput exploratory investigations.

Comparative analysis of the quality of platelet concentrates produced by apheresis procedures, platelet rich plasma, and buffy coat.

BACKGROUND: Platelet concentrates (PCs) could be prepared using either whole-blood processes or apheresis instruments. During collection, processing and storage, some biochemical and functional changes occur, which may result in quality reduction. Quality evaluation of PCs may be helpful for the precise control of platelet (PLT) inventory to reduce the risk of refractoriness and adverse effects caused by platelet transfusion. STUDY DESIGN AND METHODS: The study was aimed to evaluate the quality of PCs which were produced by five processes: apheresis (AP) procedures (using three different cell separators: Amicus, Trima Accel and MCS+ instruments), platelet rich plasma (PRP), and buffy coat (BC). A total of 100 PCs (20 of each group) were assessed in respect of routine quality control, morphology, size distribution, destroyed and activated platelets, and production of platelet-derived microparticles (PMPs). RESULTS: All PCs have satisfied the recommended quality of volume, platelet count, residual WBC count, residual RBC count, pH, and sterility according to the Chinese Technical Manual. There was no difference among the 5 groups in morphology and size of PLT and PMPs. Dynamic light scattering test showed that apheresis PCs showed peaks around 10-20 nm, but not whole blood-derived PCs. PCs prepared by Amicus had the relatively high percentage of destroyed platelet, activated platelets and PMPs than other groups. DISCUSSION: The data suggested high heterogeneity of PMPs, destroyed and activated platelets in PCs produced by different processes, which might be helpful to manage the platelet inventory for targeted use.

The platelet storage lesion, what are we working for?

BACKGROUND: Platelet concentrate (PC) transfusions are crucial in prevention and treatment of bleeding in infection, surgery, leukemia, and thrombocytopenia patients. Although the technology for platelet preparation and storage has evolved over the decades, there are still challenges in the demand for platelets in blood banks because the platelet shelf life is limited to 5 days due to bacterial contamination and platelet storage lesions (PSLs) at 20-24°C under constant horizontal agitation. In addition, the relations between some adverse effects of platelet transfusions and PSLs have also been considered. Therefore, understanding the mechanisms of PSLs is conducive to obtaining high quality platelets and facilitating safe and effective platelet transfusions. OBJECTIVE: This review summarizes developments in mechanistic research of PSLs and their relationship with clinical practice, providing insights for future research. METHODS: Authors conducted a search on PubMed and Web of Science using the professional terms "PSL" and "platelet transfusion." The obtained literature was then roughly categorized based on their research content. Similar studies were grouped into the same sections, and further searches were conducted based on the keywords of each section. RESULTS: Different studies have explored PSLs from various perspectives, including changes in platelet morphology, surface molecules, biological response modifiers (BMRs), metabolism, and proteins and RNA, in an attempt to monitor PSLs and identify intervention targets that could alleviate PSLs. Moreover, novel platelet storage conditions, including platelet additive solutions (PAS) and reconsidered cold storage methods, are explored. There are two approaches to obtaining high-quality platelets. One approach simulates the in vivo environment to maintain platelet activity, while the other keeps platelets at a low activity level in vitro under low temperatures. CONCLUSION: Understanding PSLs helps us identify good intervention targets and assess the therapeutic effects of different PSLs stages for different patients.

The effects of pen ink and surface disinfectants on red blood cells stored in plasticized polyvinylchloride transfusion bags.

BACKGROUND: Each unit of red blood cells (RBCs) produced represents a significant cost to the healthcare system. Unnecessary blood wastage should be minimized. In clinical settings, alterations to blood component bags after issue from the protected setting of the blood bank include pen markings, and those that are exposed to an infectious environment require surface disinfecting. These units may be discarded due to unclear effects on RBC quality. In this study, we investigate whether pen markings or surface disinfection negatively affects the quality of packed RBCs and whether pen ink diffuses through the blood bag. STUDY DESIGN AND METHODS: RBC bags were marked with pens (water, oil, or alcohol-based) or subjected to surface disinfection (ethanol, hydrogen peroxide [Preempt wipes], or benzalkonium chloride-based wipes [CaviWipes]) and sampled 24 h after applying the treatment and at day 42 post collection (n = 3 for each condition). The samples were analyzed for RBC in vitro quality markers. The presence of any ink in the RBC bags was investigated using mass spectrometry (n = 2). RESULTS: Data from 24 h and day 42 time points indicated no differences in RBC count, mean corpuscular volume, morphology, deformability, potassium content, or hemolysis for either pen markings or disinfectants when compared with their untreated controls (p > .05). No trace of ink was detected inside the bag. CONCLUSION: RBC units marked with ballpoint, gel, or Sharpie pens do not suffer a loss of in vitro quality, nor do RBC units which have been surface disinfected with 70% ethanol, Preempt wipes or CaviWipes.

Vesiculation in irradiated and cation-leaky-stored red blood cells.

BACKGROUND: Extracellular vesicles (EVs) are released by red blood cells (RBCs) throughout their life-span and also during hypothermic storage when they accumulate in the blood bag. We queried whether stored RBCs with increased cation permeability, either from donors with familial pseudohyperkalaemia (FP) or caused by irradiation, vesiculate more readily. STUDY DESIGN AND METHODS: Recent technical advances have revealed at least two sub-populations of MVs in RBC storage units: macrovesicles (2-6 µm) and microvesicles (1-2 µm). Using nanoparticle tracking analysis, imaging flow cytometry, and protein quantification methods, we measured and characterized vesicles released by RBCs from control and FP individuals at three different storage time-points (day 4, day 17, and day 29). The RBCs had either been stored untreated or irradiated on either day 1 or day 14 of storage. RESULTS: We found no difference in the number or size of vesicles released between cation-leaky FP RBCs and non-FP controls. Similarly, irradiated and non-irradiated RBCs showed very similar patterns of vesicle release to during cold-storage. The only significant difference in vesicle release was the increase in accumulated vesicles with length of storage time which has been reported previously. DISCUSSION: EVs in stored blood are potential contributors to adverse transfusion reactions. The number of vesicles released during 35-day hypothermic storage varies between donors and increases with storage duration. However, increased cation permeability and irradiation do not appear to affect vesicle formation during RBC cold-storage.

Regulation of kynurenine metabolism by blood donor genetics and biology impacts red cell hemolysis in vitro and in vivo.

ABSTRACT: In the field of transfusion medicine, the clinical relevance of the metabolic markers of the red blood cell (RBC) storage lesion is incompletely understood. Here, we performed metabolomics of RBC units from 643 donors enrolled in the Recipient Epidemiology and Donor Evaluation Study, REDS RBC Omics. These units were tested on storage days 10, 23, and 42 for a total of 1929 samples and also characterized for end-of-storage hemolytic propensity after oxidative and osmotic insults. Our results indicate that the metabolic markers of the storage lesion poorly correlated with hemolytic propensity. In contrast, kynurenine was not affected by storage duration and was identified as the top predictor of osmotic fragility. RBC kynurenine levels were affected by donor age and body mass index and were reproducible within the same donor across multiple donations from 2 to 12 months apart. To delve into the genetic underpinnings of kynurenine levels in stored RBCs, we thus tested kynurenine levels in stored RBCs on day 42 from 13 091 donors from the REDS RBC Omics study, a population that was also genotyped for 879 000 single nucleotide polymorphisms. Through a metabolite quantitative trait loci analysis, we identified polymorphisms in SLC7A5, ATXN2, and a series of rate-limiting enzymes (eg, kynurenine monooxygenase, indoleamine 2,3-dioxygenase, and tryptophan dioxygenase) in the kynurenine pathway as critical factors affecting RBC kynurenine levels. By interrogating a donor-recipient linkage vein-to-vein database, we then report that SLC7A5 polymorphisms are also associated with changes in hemoglobin and bilirubin levels, suggestive of in vivo hemolysis in 4470 individuals who were critically ill and receiving single-unit transfusions.