Quality Assessment of Established and Emerging Blood Components for Transfusion

Dried Plasma for Major Trauma: Past, Present, and Future

Uncontrollable bleeding is recognized as the leading cause of preventable death among trauma patients. Early transfusion of blood products, especially plasma replacing crystalloid and colloid solutions, has been shown to increase survival of severely injured patients. However, the requirements for cold storage and thawing processes prior to transfusion present significant logistical challenges in prehospital and remote areas, resulting in a considerable delay in receiving thawed or liquid plasma, even in hospitals. In contrast, freeze- or spray-dried plasma, which can be massively produced, stockpiled, and stored at room temperature, is easily carried and can be reconstituted for transfusion in minutes, provides a promising alternative. Drawn from history, this paper provides a review of different forms of dried plasma with a focus on in vitro characterization of hemostatic properties, to assess the effects of the drying process, storage conditions in dry form and after reconstitution, their distinct safety and/or efficacy profiles currently in different phases of development, and to discuss the current expectations of these products in the context of recent preclinical and clinical trials. Future research directions are presented as well.

Accessory-cell-free differentiation of hematopoietic stem and progenitor cells into mature red blood cells

BACKGROUND AIMS

The culture and ex vivo engineering of red blood cells (RBCs) can help characterize genetic variants, model diseases, and may eventually spur the development of applications in transfusion medicine. In the last decade, improvements to the in vitro production of RBCs have enabled efficient erythroid progenitor proliferation and high enucleation levels from several sources of hematopoietic stem and progenitor cells (HSPCs). Despite these advances, there remains a need for refining the terminal step of in vitro human erythropoiesis, i.e., the terminal maturation of reticulocytes into erythrocytes, so that it can occur without feeder or accessory cells and animal-derived components.

METHODS

Here, we describe the near-complete erythroid differentiation of cultured RBCs (cRBCs) from adult HSPCs in accessory-cell-free and xeno-free conditions.

RESULTS

The approach improves post-enucleation cell integrity and cell survival, and it enables subsequent storage of cRBCs for up to 42 days in classical additive solution conditions without any specialized equipment.

CONCLUSIONS

We foresee that these improvements will facilitate the characterization of RBCs derived from gene-edited HSPCs.

An insight to the internal quality control of blood components separated using the latest whole blood collection and processing systems: Experience from a tertiary care hospital blood transfusion service in Eastern India

BACKGROUND

With blood component therapy becoming the standard of care in transfusion medicine globally, the quality control (QC) of these components has become a routine and mandatory program in all blood centers. Extensive utilization of blood components has been observed in our multidisciplinary tertiary care hospital. We use quadruple bag systems and automated component extraction facilities for collection and processing of whole blood (WB). In this study, we analyzed our data relating to QC of all blood components which we prepare and issue for transfusion.

MATERIALS AND METHODS

The retrospective 5-year study comprised 47,430 WB collections which were separated into blood components using quadruple bags and automated component extraction machine. A total of 90 units of WB were processed into blood components for the machine calibration and validation. Routine use of the system was started once the calibration and validation results were acceptable. At least 1% of each component prepared was subjected to QC as per departmental standard operating procedures. Statistical analysis was done using the SPSS statistical package.

RESULTS

The mean volume, hematocrit (Hct), platelet (PLT), and white blood cell (WBC) in 350 and 450 mL WB units were 394.63 mL, 39.43%, 0.93 × 1011, and 3.12 × 109 and 507.75 mL, 40.72%, 1.13 × 1011, and 3.45 × 109, respectively, with mean recovery of PLT and WBC in buffy coat being 95.54% and 68.63% and 97.87% and 74.51%, respectively. As high as 89.91% RBC recovery was noted in the packed red blood cell units which were subjected to QC. QC of random donor platelets was performed in 979 (2.36%) units with acceptable results. The mean fibrinogen and FVIII values were estimated to be 469.17 mg and 217.34 IU (1.07 IU/mL) and 600.21 mg and 273.39 IU (1.11 IU/mL) in fresh frozen plasma units prepared from 350 and 450 mL WB, respectively. A total of 578 (1.62%) units of cryoprecipitate were investigated for QC with favorable results.

CONCLUSION

We conclude that QC data generated in this study will provide invaluable information about the performance of the latest blood collection systems. QC of all blood components under study complied with both national and international standards. We opine that all blood centers should establish a complete QC program and adhere to departmental protocols and manufacturer's instructions for its execution and effective outcome.

Retention of hemostatic and immunological properties of frozen plasma and COVID-19 convalescent apheresis fresh-frozen plasma produced and freeze-dried in Canada

BACKGROUND

Randomized clinical trial data show that early plasma transfusion may save lives among trauma patients. Supplying plasma in remote environments is logistically challenging. Freeze-dried plasma (FDP) offers a possible solution.

STUDY DESIGN AND METHODS

A Terumo BCT plasma freeze-drying system was evaluated. We compared pooled frozen plasma (FP) units with derived Terumo BCT FDP (TFDP) units and pooled COVID-19 convalescent apheresis fresh-frozen plasma (CC-AFFP) with derived CC-TFDP units. Parameters measured were: coagulation factors (F) II; V; VII; VIII; IX; XI; XIII; fibrinogen; Proteins C (PC) and S (PS); antithrombin (AT); α₂ -antiplasmin (α₂ AP); ADAMTS13; von Willebrand Factor (vWF); thrombin-antithrombin (TAT); D-dimer; activated complement factors 3 (C3a) and 5 (C5a); pH; osmolality; prothrombin time (PT); and activated partial thromboplastin time (aPTT). Antibodies to SARS-CoV-2 in CC-AFFP and CC-TFDP units were compared by plaque reduction assays and viral protein immunoassays.

RESULTS

Most parameters were unchanged in TFDP versus FP or differed ≤15%. Mean aPTT, PT, C3a, and pH were elevated 5.9%, 6.9%, 64%, and 0.28 units, respectively, versus FP. CC-TFDP showed no loss of SARS-CoV-2 neutralization titer versus CC-AFFP and no mean signal loss in most pools by viral protein immunoassays.

CONCLUSION

Changes in protein activities or clotting times arising from freeze-drying were <15%. Although C3a levels in TFDP were elevated, they were less than literature values for transfusable plasma. SARS-CoV-2-neutralizing antibody titers and viral protein binding levels were largely unaffected by freeze-drying. In vitro characteristics of TFDP or CC-TFDP were comparable to their originating plasma, making future clinical studies appropriate.

Blood transfusion demands in a tertiary otolaryngology, head and neck centre: A 5-year retrospective cohort study

OBJECTIVES

To retrospectively analyse and report the utilisation of red blood cell (RBC) transfusion in a tertiary otolaryngology, head and neck centre in the United Kingdom.

BACKGROUND

Twenty-seven per cent of RBC transfusions were for surgical indications in a 2014 England and North Wales survey. Currently, there is limited literature on RBC transfusions in Otolaryngology.

METHODS/MATERIALS

All inpatients admitted primarily under the care of the Otolaryngology, Head and Neck service between January 2015 and December 2019 were analysed. The primary outcomes of interest were number of units of RBC transfused over 5 years and distribution across clinical indications. Secondary outcome measure was cost of RBC transfusions over the same time period.

RESULTS

Most patients receiving transfusions are aged in their sixth and seventh decades. Epistaxis patients utilised 105 RBC units over the 5 years (56% of total RBC units) with emergency epistaxis accounting for 78% of use. Post-operative Head & Neck Cancer surgery with and without reconstruction required 47 RBC units over 5 years (25% of total RBC units). The mean cost incurred by the department over the 5-year period was £6171.49 (SD 1460.25). The cost has fallen by over £2000 over the 5-year period.

CONCLUSION

Blood transfusion use has fluctuated over the last 5 years. Epistaxis and post-operative Head and Neck cancer cases account for significant use compared with other patient groups. Prehabilitation strategies will add value towards mitigating future consumption of RBC.

Challenging the 30-min rule for thawed plasma

BACKGROUND AND OBJECTIVES

Frozen plasma (FP) is thawed prior to transfusion and stored for ≤5 days at 1-6°C. The effect of temperature excursions on the quality and safety of thawed plasma during 5-day storage was determined.

MATERIALS AND METHODS

Four plasma units were pooled, split and stored at ≤-18°C for ≤90 days. Test units T30 and T60 were exposed to 20-24°C (room temperature [RT]) for 30 or 60 min, respectively, on days 0 and 2 of storage. Negative and positive control units remained refrigerated or at RT for 5 days, respectively. On Day 5, test units were exposed once to RT for 5 h. Quality assays included stability of coagulation factors FV, FVII, FVIII, fibrinogen and prothrombin time. Bacterial growth was performed in units inoculated with ~1 CFU/ml or ~100 CFU/ml of Serratia liquefaciens, Pseudomonas putida, Pseudomonas aeruginosa or Staphylococcus epidermidis on Day 0.

RESULTS

Testing results of all quality parameters were comparable between T30 and T60 units (p < 0.05). Serratia liquefaciens proliferated in cold-stored plasma, while P. putida showed variable viability. Serratia epidermidis and P. aeruginosa survived but did not grow in cold-stored plasma. Positive and negative controls showed expected results. Overall, no statistical differences in bacterial concentration between T30 and T60 units were observed (p < 0.05).

CONCLUSION

Multiple RT exposures for 30 or 60 min do not affect the stability of coagulation factors or promote bacterial growth in thawed plasma stored for 5 days. It is therefore safe to expose thawed plasma to uncontrolled temperatures for limited periods of 60 min.

Evaluation of quality matrix when practice changed from triple bags to quadruple (top and bottom) bags: In vitro analysis of blood components!

BACKGROUND:

As a part of continuous quality initiatives, while moving from triple bags to quadruple bags, we undertook a study to compare platelet-rich plasma (PRP) and buffy-coat (BC) methods with respect to all blood components (red blood cells [RBCs], random donor platelet concentrate [RDPC], and fresh frozen plasma [FFP]) prepared by PRP and BC methods.

MATERIALS AND METHODS:

It was a prospective analysis of different physical and quality parameters of RDPC, RBC, and FFP prepared out of 100 whole blood (WB) donations. Of these, 50 WB units were processed by PRP method using Triple bags and 50 WB units by BC method, using quadruple (top and bottom) bags, with an attached integral filter.

RESULTS:

RBC prepared by BC method had higher hematocrit (61.3 ± 1.91% vs. 56.03 ± 3.37%; P < 0.05) and lower white blood cell (WBC) contamination (6.3 × 10⁴ ± 6.1 vs. 5.41 × 10⁵ ± 2.5; P < 0.05) in comparison to prepared by PRP method. Higher PLT yield (7.67 × 10¹⁰ ± 1.8 vs. 6.47 × 10¹⁰ ± 1.5; P < 0.05) and lower WBC count (8.24 × 10³ ± 1.1 vs. 1.5 × 10⁴ ± 2.1; P < 0.05) was observed in RDPC prepared by BC method than PRP derived. CD62P expression was lower in RDPC prepared by BC method (31.46 ± 9.7%; P < 0.05) as compared to PRP method (43.35 ± 12.5%; P < 0.05). The BC method also resulted in increased plasma yield (210.56 ± 18.54 ml vs. 187.92 ± 12.93 ml; P < 0.05) in FFP in comparison to PRP method.

CONCLUSION:

The blood components produced from WB by the BC method have laboratory variables suggestive of superior quality than those produced by the PRP method.

Research progress of using micro/nanomotors in the detection and therapy of diseases related to the blood environment

Micro/nanomotors bring new possibilities for the detection and therapy of diseases related to the blood environment with their unique motion effect. This work reviews the research progress of using micro/nanomotors in the detection and therapy of diseases related to the blood environment. First, we outline the advantages of using micro/nanomotors in blood-related disease detection. To be specific, the motion capability of micro/nanomotors can increase plasma or blood fluid convection and accelerate the interaction between the sample and the capture probe. This allows the effective reduction of the amount of reagents and treatment steps. Therefore, the application of micro/nanomotors significantly improves the analytical performance. Second, we discuss the key challenges and future prospects of micro/nanomotors in the treatment of blood-environment related diseases. It is very important to design a unique treatment plan according to the etiology and specific microenvironment of the disease. The next generation of micro/nanomotors is expected to bring exciting progress to the detection and therapy of blood-environment related diseases.

Post-expiry stability of freeze-dried plasma under field conditions - Can shelf life be extended?

BACKGROUND

This prospective study evaluated the effect of routine, uncontrolled, Israeli field storage conditions on the safety and efficacy of Lyo-Plas N Freeze-Dried Plasma (FDP) at the end of the manufacturer's shelf life, and up to 24 months post expiry. Clotting factors V, VIII and XI, proteins S, C, fibrinogen, PTT, ATIII, VWF, and INR as well as TEG, DDM, residual moisture, pH, and sterility of FDP returned from field units after uncontrolled storage were evaluated.

STUDY DESIGN AND METHODS

Parameters measured at the end of manufacturer shelf life, as well as 6, 12, 18, and 24 months after expiry, were compared to those of freshly supplied FDP doses.

RESULTS

Changes were found when comparing freshly supplied FDP to all field-stored groups in INR, PT, PTT, pH, fibrinogen, and factor VIII. A significant change was also seen in Factor XI in the 12, 18, and 24 months post-expiry samples, Factor V and R in the 24 months post-expiry samples, MA in the 12, 24 months post-expiry group, and Protein C in the 18 months post-expiry group. An increase in the residual moisture from 0.90% in freshly supplied FDP to 1.35% in 24 months post-expiry FDP.; all p < .05. No growth was found in sterility analysis.

CONCLUSION

Despite uncontrolled field storage conditions, the findings demonstrate that the safety and efficacy of FDP units, stored in uncontrolled conditions are only slightly affected, even beyond their expiration date. This information allows consideration of possibly extending the shelf life.

Stepping stones to the future of haemoglobin-based blood products: clinical, preclinical and innovative examples

Critical overview of the different oxygen therapeutics developed so far to be used when donor blood is not available.

Effects of refrigerated storage on hemostatic stability of four canine plasma products

OBJECTIVE

To assess clotting times, coagulation factor activities, sterility, and thromboelastographic parameters of liquid plasma (LP), thawed fresh frozen plasma (FFP-T), and 2 novel formulations of freeze-dried plasma (FDP) stored refrigerated over 35 days.

SAMPLE

6 units of canine LP and FFP-T from a commercial animal blood bank and 5 units each of 2 formulations of canine FDP.

PROCEDURES

Prothrombin time; activated partial thromboplastin time; activities of coagulation factors II, V, VII, VIII, IX, X, XI, and XII; and thromboelastographic parameters were determined for each product on days 0 (baseline), 3, 7, 14, 21, 28, and 35. For each day, a sample of each product was also submitted for aerobic bacterial culture.

RESULTS

Small changes in coagulation factor activities and mild increased time to initial clot formation in LP and FFP-T were noted over the 35-day storage period. Activities of factor VIII in FDP1 and factor XII in FDP2 were < 50% at baseline but varied throughout. Compared with FFP-T, time to initial clot formation was increased and clot strength was preserved or increased for the FDPs throughout the study. One FDP had decreased pH, compared with other products. No plasma product yielded bacterial growth.

CONCLUSIONS AND CLINICAL RELEVANCE

Liquid plasma and FFP-T would be reasonable to use when stored refrigerated for up to 35 days. Both FDP products showed variability in coagulation factor activities. Studies investigating the usefulness of these plasma products (FDPs) in dogs and the variable days of refrigerated storage (all products) are warranted. (Am J Vet Res 2020;81:964-972).

Cell-Based Therapy Manufacturing in Stirred Suspension Bioreactor: Thoughts for cGMP Compliance

Cell-based therapy (CBT) is attracting much attention to treat incurable diseases. In recent years, several clinical trials have been conducted using human pluripotent stem cells (hPSCs), and other potential therapeutic cells. Various private- and government-funded organizations are investing in finding permanent cures for diseases that are difficult or expensive to treat over a lifespan, such as age-related macular degeneration, Parkinson’s disease, or diabetes, etc. Clinical-grade cell manufacturing requiring current good manufacturing practices (cGMP) has therefore become an important issue to make safe and effective CBT products. Current cell production practices are adopted from conventional antibody or protein production in the pharmaceutical industry, wherein cells are used as a vector to produce the desired products. With CBT, however, the “cells are the final products” and sensitive to physico- chemical parameters and storage conditions anywhere between isolation and patient administration. In addition, the manufacturing of cellular products involves multi-stage processing, including cell isolation, genetic modification, PSC derivation, expansion, differentiation, purification, characterization, cryopreservation, etc. Posing a high risk of product contamination, these can be time- and cost- prohibitive due to maintenance of cGMP. The growing demand of CBT needs integrated manufacturing systems that can provide a more simple and cost-effective platform. Here, we discuss the current methods and limitations of CBT, based upon experience with biologics production. We review current cell manufacturing integration, automation and provide an overview of some important considerations and best cGMP practices. Finally, we propose how multi-stage cell processing can be integrated into a single bioreactor, in order to develop streamlined cGMP-compliant cell processing systems.

Assessment of extracellular vesicles using IFC for application in transfusion medicine

Extracellular vesicles (EVs) have been shown to be involved in various physiological and pathophysiological processes. With respect to Transfusion Medicine, the accumulation of EVs in blood products during hypothermic storage is an indicator of the storage lesion and reportedly correlates with adverse effects after transfusion, including but not limited to immunomodulation, activation of coagulation, endothelial activation, and others. To optimally reduce such an impact on blood product quality degradation and improve post-transfusion outcomes, better methods for detection, enumeration, characterisation by size and phenotype, and functional involvement of EVs in different pathophysiological and physiological processes are required. Currently, Imaging Flow Cytometry (IFC) technology provides the most comprehensive assessment of EV subsets in different body fluids. The unique ability of IFC to detect EVs of 20 nm size by registration of a single pixel of fluorescence signal makes this approach highly promising for comprehensive studies of EVs. In this review, we will focus on the recent breakthrough and advantages of using the ImageStream^X MKII IFC platform for the detection and characterisation of EVs and its future prospects for routine application of IFC in Transfusion Medicine.

Donor-dependent aging of young and old red blood cell subpopulations: Metabolic and functional heterogeneity

BACKGROUND

Characteristics of red blood cells (RBCs) are influenced by donor variability. This study assessed quality and metabolomic variables of RBC subpopulations of varied biologic age in red blood cell concentrates (RCCs) from male and female donors to evaluate their contribution to the storage lesion.

STUDY DESIGN AND METHODS

Red blood cell concentrates from healthy male (n = 6) and female (n = 4) donors were Percoll separated into less dense ("young", Y-RCCs) and dense ("old", O-RCCs) subpopulations, which were assessed weekly for 28 days for changes in hemolysis, mean cell volume (MCV), hemoglobin concentration (MCHC), hemoglobin autofluorescence (HGB), morphology index (MI), oxygen affinity (p50), rigidity, intracellular reactive oxygen species (ROS), calcium ([Ca²⁺ ]), and mass spectrometry-based metabolomics.

RESULTS

Young RCCs having disc-to-discoid morphology showed higher MCV and MI, but lower MCHC, HGB, and rigidity than O-RCCs, having discoid-to-spheroid shape. By Day 14, Y-RCCs retained lower hemolysis and rigidity and higher p50 compared to O-RCCs. Donor sex analyses indicated that females had higher MCV, HGB, ROS, and [Ca²⁺ ] and lower hemolysis than male RBCs, in addition to having a decreased rate of change in hemolysis by Day 28. Metabolic profiling indicated a significant sex-related signature across all groups with increased markers of high membrane lipid remodeling and antioxidant capacity in Y-RCCs, whereas O-RCCs had increased markers of oxidative stress and decreased coping capability.

CONCLUSION

The structural, functional, and metabolic dissimilarities of Y-RCCs and O-RCCs from female and male donors demonstrate RCC heterogeneity, where RBCs from females contribute less to the storage lesion and age slower than males.

Hemoglobin-based Oxygen Carriers: Current State-of-the-art and Novel Molecules

In blood, the primary role of red blood cells (RBCs) is to transport oxygen via highly regulated mechanisms involving hemoglobin (Hb). Hb is a tetrameric porphyrin protein comprising of two α- and two β-polypeptide chains, each containing an iron-containing heme group capable of binding one oxygen molecule. In military as well as civilian traumatic exsanguinating hemorrhage, rapid loss of RBCs can lead to suboptimal tissue oxygenation and subsequent morbidity and mortality. In such cases, transfusion of whole blood or RBCs can significantly improve survival. However, blood products including RBCs present issues of limited availability and portability, need for type matching, pathogenic contamination risks, and short shelf-life, causing substantial logistical barriers to their prehospital use in austere battlefield and remote civilian conditions. While robust research is being directed to resolve these issues, parallel research efforts have emerged toward bioengineering of semisynthetic and synthetic surrogates of RBCs, using various cross-linked, polymeric, and encapsulated forms of Hb. These Hb-based oxygen carriers (HBOCs) can potentially provide therapeutic oxygenation when blood or RBCs are not available. Several of these HBOCs have undergone rigorous preclinical and clinical evaluation, but have not yet received clinical approval in the USA for human use. While these designs are being optimized for clinical translations, several new HBOC designs and molecules have been reported in recent years, with unique properties. The current article will provide a comprehensive review of such HBOC designs, including current state-of-the-art and novel molecules in development, along with a critical discussion of successes and challenges in this field.

Prolonged (post-thaw) shelf life of -80°C frozen AB apheresis plasma

BACKGROUND

Early plasma transfusion is important in the treatment of patients with major hemorrhage. Prolonged shelf life of AB type frozen −80°C and cold‐stored (4°C) deep frozen plasma (DFP) will improve strategic stock management, minimize need for resupply, and make pre‐hospital implementation more feasible.

METHODS AND MATERIALS

Plasma products type AB of different age and origin (−30°C Fresh Frozen [(FFP], −80°C DFP [short (±1 year) and long (±7 year)] stored) were thawed (Day 0), stored at 4°C, and sampled on Days 7 and 14. Additionally, samples of plasma containing blood products (Octaplas LG®, whole blood and platelets) were compared for coagulation factor activity, phospholipid clotting time (PPL), and kaolin TEG during 4°C or 22°C storage.

RESULTS

Coagulation profiles of FFP, short‐ and long‐stored −80°C DFP were not significantly different after thaw. Cold storage did not affect fibrinogen, Protein C, and Antithrombin III activities whereas factor V, VII, VIII, and Protein S decreased in all blood products. After 14 days DFP still meets the guidelines for clinical use, except for Protein S (0.4 IU/mL). With exception of Octaplas LG®, phospholipid activity and TEG coagulation were similar between plasma containing blood components during storage.

CONCLUSION

AB DFP quality was unaffected by almost 7 years of frozen storage. Quality of thawed 14‐day stored AB DFP met, with exception of Protein S, all minimal guidelines which implies that its quality is sufficient for use in the (pre)‐hospital (military) environment for treatment of major hemorrhage.

Status analysis and evaluation of the blood scrap rate from 2015-2017 for a blood center in China

OBJECTIVES

The objective of this study was to ascertain the current conditions and development in the past three years of clinical transfusion practice in Nanjing, Jiangsu province, China.

MATERIALS AND METHODS

Blood quality control practices and the blood production scrap rate from 2015-2017 were monitored and measured using different quality statistics and management tools.

RESULTS

The causes of unqualified and scrapped blood during blood collection and supply were analyzed and evaluated. The analysis of the key indices for blood component quality control showed that the qualified rate of FVIII activity (from fresh frozen plasma) was 54.55%, which failed to meet the threshold of 75%. Retrospective analysis of conventional blood scrapping factors showed that laboratory scraps accounted for the majority. The composition ratio of TTI screening results included ALT (31.91%), HBV (21.92%), TP (12.15%), NAT (10.78%), HCV (8.45%), and HIV (7.43%). Retrospective analysis of unconventional blood scrapping factors showed that the total unconventional blood depletion rate was 0.565%. Insufficient or small quantities of collected blood was the most important factor related to unconventional scrapping. The blood donor and blood hospital service satisfaction rates were over 95% and 90%, respectively, which achieved the quality target.

CONCLUSIONS

Nonconforming product control was proposed and determined as the urgent theme of the first QCC. It is necessary for blood stations to effectively control blood scrapping, which can reduce the cost of blood collection, protect the blood donation of unpaid blood donors, increase the rate of repeated blood donation, and improve blood safety.

Development of a flow standard to enable highly reproducible measurements of deformability of stored red blood cells in a microfluidic device

BACKGROUND

Great deformability allows red blood cells (RBCs) to flow through narrow capillaries in tissues. A number of microfluidic devices with capillary-like microchannels have been developed to monitor storage-related impairment of RBC deformability during blood banking operations. This proof-of-concept study describes a new method to standardize and improve reproducibility of the RBC deformability measurements using one of these devices.

STUDY DESIGN AND METHODS

The rate of RBC flow through the microfluidic capillary network of the microvascular analyzer (MVA) device made of polydimethylsiloxane was measured to assess RBC deformability. A suspension of microbeads in a solution of glycerol in phosphate-buffered saline was developed to be used as an internal flow rate reference alongside RBC samples in the same device. RBC deformability and other in vitro quality markers were assessed weekly in six leukoreduced RBC concentrates (RCCs) dispersed in saline-adenine-glucose-mannitol additive solution and stored over 42 days at 4°C.

RESULTS

The use of flow reference reduced device-to-device measurement variability from 10% to 2%. Repeated-measure analysis using the generalized estimating equation (GEE) method showed a significant monotonic decrease in relative RBC flow rate with storage from Week 0. By the end of storage, relative RBC flow rate decreased by 22 ± 6% on average.

CONCLUSIONS

The suspension of microbeads was successfully used as a flow reference to increase reproducibility of RBC deformability measurements using the MVA. Deformability results suggest an early and late aging phase for stored RCCs, with significant decreases between successive weeks suggesting a highly sensitive measurement method.

Lyophilized Autologous Serum Eyedrops: Experimental and Comparative Study

PURPOSE

To analyze the biological stability of autologous serum eyedrops after lyophilization.

DESIGN

Prospective, comparative experimental study.

METHODS

This was a comparative study with serum obtained from 12 healthy volunteers. The concentrations of different epitheliotropic factors (eg, transforming growth factor-β [TGF-β1], epidermal growth factor [EGF], platelet-derived growth factor AB [PDGF-AB], and albumin) were measured in fresh and lyophilized serum. The samples were studied after serum preparation (fresh serum) and immediately after saline solution reconstitution of lyophilized serum (0), 15, and 30 days later. The biological effects of both serum samples were also compared on conjunctival and corneal cell cultures. The pH, osmolarity, and serum density were also determined.

RESULTS

No significant differences were found in the concentration of growth factors between fresh serum and re-dissolved serum samples after lyophilization. The concentration of growth factors remained stable during 1 month at 4°C in re-dissolved lyophilized form with saline solution. No differences were found related to osmolarity, pH, and density between fresh and lyophilized serum. In addition, no differences were found on the conjunctival and corneal cells proliferation and differentiation in cells cultures between either serum preparation.

CONCLUSIONS

The properties of autologous serum remain after lyophilization. The lyophilized serum can be easily stored without temperature restrictions and easily reconstituted for preparation of eyedrops for standard clinical use.

Opportunities for standardization of cold stored, low-titre group O WB products

Interest in the use of cold-stored low-titre, group O whole blood (LTO-WB) in civilian trauma medicine has motivated regional and national blood services to explore the operational implications of providing this product to their hospital customers. While simpler to produce, store and administer than conventional blood components, LTO-WB is only distributed by a limited number of civilian blood services to date. To improve the availability of LTO-WB, there are still a number of clinical and basic research challenges that need to be addressed including 1. Standardization of the methods and definitions for what constitutes "low-titre" whole blood; 2. Updating regulatory standards for the in vitro quality of cold stored whole blood; 3. Development of standards for the post-storage component separation of red blood cells from cold stored whole blood; and 4. Optimization of the logistics for collection and distribution of cold stored whole blood in regional and national blood systems. The main objective of this concise overview is to highlight the opportunities for future research and product development efforts that will improve the availability of standardised LTO-WB products in emergency cases to the benefit of all concerned.

The effect of platelet storage temperature on haemostatic, immune, and endothelial function: potential for personalised medicine

Reports from both adult and paediatric populations indicate that approximately two-thirds of platelet transfusions are used prophylactically to prevent bleeding, while the remaining one-third are used therapeutically to manage active bleeding. These two indications, prophylactic and therapeutic, serve two very distinct purposes and therefore will have two different functional requirements. In addition, disease aetiology in a given patient may require platelets with different functional characteristics. These characteristics can be derived from the various manufacturing methods used in platelet product production, including collection methods, processing methods, and storage options. The iterative combinations of manufacturing methods can result in a number of unique platelet products with different efficacy and safety profiles, which could potentially be used to benefit patient populations by meeting diverse clinical needs. In particular, cold storage of platelet products causes many biochemical and functional changes, of which the most notable characterised to date include increased haemostatic activity and altered expression of molecules inherent to platelet:leucocyte interactions. The in vivo consequences, both short- and long-term, of these molecular and cellular cold-storage-induced changes have yet to be clearly defined. Elucidation of these mechanisms would potentially reveal unique biologies that could be harnessed to provide more targeted therapies. To this end, in this new era of personalised medicine, perhaps there is an opportunity to provide individual patients with platelet products that are tailored to their clinical condition and the specific indication for transfusion.

Review of current transfusion therapy and blood banking practices

Transfusion Medicine is a dynamically evolving field. Recent high-quality research has reshaped the paradigms guiding blood transfusion. As increasing evidence supports the benefit of limiting transfusion, guidelines have been developed and disseminated into clinical practice governing optimal transfusion of red cells, platelets, plasma and cryoprecipitate. Concepts ranging from transfusion thresholds to prophylactic use to maximal storage time are addressed in guidelines. Patient blood management programs have developed to implement principles of patient safety through limiting transfusion in clinical practice. Data from National Hemovigilance Surveys showing dramatic declines in blood utilization over the past decade demonstrate the practical uptake of current principles guiding patient safety. In parallel with decreasing use of traditional blood products, the development of new technologies for blood transfusion such as freeze drying and cold storage has accelerated. Approaches to policy decision making to augment blood safety have also changed. Drivers of these changes include a deeper understanding of emerging threats and adverse events based on hemovigilance, and an increasing healthcare system expectation to align blood safety decision making with approaches used in other healthcare disciplines.

Methodological considerations for linked blood donor-component-recipient analyses in transfusion medicine research

In recent years, there has been a concerted effort to improve our understanding of the quality and effectiveness of transfused blood components. The expanding use of large datasets built from electronic health records allows the investigation of potential benefits or adverse outcomes associated with transfusion therapy. Together with data collected on blood donors and components, these datasets permit an evaluation of associations between donor or blood component factors and transfusion recipient outcomes. Large linked donor-component recipient datasets provide the power to study exposures relevant to transfusion efficacy and safety, many of which would not otherwise be amenable to study for practical or sample size reasons. Analyses of these large blood banking-transfusion medicine datasets allow for characterization of the populations under study and provide an evidence base for future clinical studies. Knowledge generated from linked analyses have the potential to change the way donors are selected and how components are processed, stored and allocated. However, unrecognized confounding and biased statistical methods continue to be limitations in the study of transfusion exposures and patient outcomes. Results of observational studies of blood donor demographics, storage age, and transfusion practice have been conflicting. This review will summarize statistical and methodological challenges in the analysis of linked blood donor, component, and transfusion recipient outcomes.

Blood manufacturing methods affect red blood cell product characteristics and immunomodulatory activity

Transfusion of red cell concentrates (RCCs) is associated with increased risk of adverse outcomes that may be affected by different blood manufacturing methods and the presence of extracellular vesicles (EVs). We investigated the effect of different manufacturing methods on hemolysis, residual cells, cell-derived EVs, and immunomodulatory effects on monocyte activity. Thirty-two RCC units produced using whole blood filtration (WBF), red cell filtration (RCF), apheresis-derived (AD), and whole blood-derived (WBD) methods were examined (n = 8 per method). Residual platelet and white blood cells (WBCs) and the concentration, cell of origin, and characterization of EVs in RCC supernatants were assessed in fresh and stored supernatants. Immunomodulatory activity of RCC supernatants was assessed by quantifying monocyte cytokine production capacity in an in vitro transfusion model. RCF units yielded the lowest number of platelet and WBC-derived EVs, whereas the highest number of platelet EVs was in AD (day 5) and in WBD (day 42). The number of small EVs (<200 nm) was greater than large EVs (≥200 nm) in all tested supernatants, and the highest level of small EVs were in AD units. Immunomodulatory activity was mixed, with evidence of both inflammatory and immunosuppressive effects. Monocytes produced more inflammatory interleukin-8 after exposure to fresh WBF or expired WBD supernatants. Exposure to supernatants from AD and WBD RCC suppressed monocyte lipopolysaccharide-induced cytokine production. Manufacturing methods significantly affect RCC unit EV characteristics and are associated with an immunomodulatory effect of RCC supernatants, which may affect the quality and safety of RCCs.

Optimizing whole blood storage: hemostatic function of 35-day stored product in CPD, CP2D, and CPDA-1 anticoagulants

BACKGROUND

Transitioning from whole blood (WB) to components developed from efforts to maximize donor yield. Components are advantageous for specific derangements, but treating hemorrhage with components requires significantly more volume to provide similar effects to WB. Because storage lesion and waste remain problematic, this study examined hemostatic function of refrigerated WB stored for 35 days in anticoagulants citrate-phosphate-dextrose-adenosine (CPDA-1), citrate-phosphate-dextrose (CPD), or citrate-phosphate-double dextrose (CP2D).

METHODS

Refrigerated WB units from healthy donors were sampled over 35 days. Global hemostatic parameters were measured by thromboelastometry, thrombogram, platelet aggregometry, and platelet adhesion to collagen under shear conditions. The effects of transfusion filtration and mixing 35-day stored product with fresh WB were evaluated.

RESULTS

Countable platelets declined as aggregation clusters appeared in microscopy. While gross platelet agonist-induced aggregation declined over time, normalization revealed aggregation responses in remaining platelets. Peak thrombin generation increased over time. Clot strength diminished over storage in tissue factor-activated samples (normalized by filtration of aggregates). Functional fibrinogen responses remained consistent throughout. Filtration was necessary to maintain consistent platelet adhesion to collagen beyond collection day. Few differences were observed between anticoagulants, and stored/fresh mixing studies normalized coagulation parameters.

CONCLUSIONS

WB is easier to collect, store, and transfuse. WB provides platelets, an oft-neglected, critical resuscitation component, but their individual numbers decline as aggregates appear, resulting in diminished coagulation response. WB has better performance in these assays when examined at earlier time points, but expirations designated to specific anticoagulants appear arbitrary for hemostatic functionality, as little changes beyond 21 days regardless of anticoagulant.

Effects of storage over a 36-month period on coagulation factors in a canine plasma product obtained by use of plasmapheresis

OBJECTIVE

To evaluate stability of coagulation factors in canine plasma obtained by use of plasmapheresis and stored over a 36-month period.

SAMPLE

Canine plasma obtained by use of plasmapheresis acquired from a commercial blood bank.

PROCEDURES

Coagulation testing for fibrinogen concentration and activity of factors II, V, VII, VIII, and IX and von Willebrand factor was performed on canine plasma obtained by use of plasmapheresis. Samples were obtained for testing at 6-month intervals from plasma stored for up to 36 months.

RESULTS

A simple mixed linear regression model was created for each analysis. Median value for the fibrinogen concentration was > 150 mg/dL for all time points, except at 467, 650, and 1,015 days of storage. Median value for factor VIII was > 70% only at 650 days. Median value for factor V was > 50% through 650 days. Median value for factors VII and X was > 50% through 833 days, and median value for factors II and VII was > 50% through 1,015 days. Median value for von Willebrand factor was > 50% for the entire study (1,198 days). Median value for factor X was always < 50%.

CONCLUSIONS AND CLINICAL RELEVANCE

Coagulation factors degraded over time at variable rates, and all labile factors remained at > 50% activity for longer than 1 year. Plasma collected by plasmapheresis potentially offers prolonged life span of some clotting factors. Plasmapheresis is an acceptable form of canine plasma collection for transfusion purposes, and further studies should be performed to determine all of its benefits.

Effect of donor, component, and recipient characteristics on hemoglobin increments following red blood cell transfusion

Significant research has focused individually on blood donors, product preparation and storage, and optimal transfusion practice. To better understand the interplay between these factors on measures of red blood cell (RBC) transfusion efficacy, we conducted a linked analysis of blood donor and component data with patients who received single-unit RBC transfusions between 2008 and 2016. Hemoglobin levels before and after RBC transfusions and at 24- and 48-hour intervals after transfusion were analyzed. Generalized estimating equation linear regression models were fit to examine hemoglobin increments after RBC transfusion adjusting for donor and recipient demographic characteristics, collection method, additive solution, gamma irradiation, and storage duration. We linked data on 23 194 transfusion recipients who received one or more single-unit RBC transfusions (n = 38 019 units) to donor demographic and component characteristics. Donor and recipient sex, Rh-D status, collection method, gamma irradiation, recipient age and body mass index, and pretransfusion hemoglobin levels were significant predictors of hemoglobin increments in univariate and multivariable analyses (P < .01). For hemoglobin increments 24 hours after transfusion, the coefficient of determination for the generalized estimating equation models was 0.25, with an estimated correlation between actual and predicted values of 0.5. Collectively, blood donor demographic characteristics, collection and processing methods, and recipient characteristics accounted for significant variation in hemoglobin increments related to RBC transfusion. Multivariable modeling allows the prediction of changes in hemoglobin using donor-, component-, and patient-level characteristics. Accounting for these factors will be critical for future analyses of donor and component factors, including genetic polymorphisms, on posttransfusion increments and other patient outcomes.

Clotting factor activity in fresh frozen plasma after thawing with a new radio wave thawing device

BACKGROUND

Massive hemorrhage usually results in rapid need of blood products. Patients in need of fresh frozen plasma (FFP) might benefit from shorter thawing times using a novel radio wave device. So far, only one study on the prototype has been published. Activities of clotting factors after thawing FFP with the radio wave device and with a system using water cushions were compared. This is the first study analyzing the quality of FFP using the fully developed radio wave thawing device UFT100.

STUDY DESIGN AND METHODS

Thirty FFP units were thawed with the UFT100 and the Plasmatherm machine. Various clotting factors and inhibitors were analyzed before freezing, immediately after thawing, and after a 48-hour storage period at +4°C.

RESULTS

After thawing, all factor activities were within normal ranges regardless of the thawing procedure. We observed significant differences in nearly all clotting factor activities regarding time as effector, whereas thawing with the Plasmatherm machine led to a significant decrease (>10%) only in factor V activity compared to the UFT100.

CONCLUSIONS

Immediately after rapid thawing with the UFT100, all FFP units contained adequate coagulation factor activities to maintain hemostatic activity. The UFT100 does not deteriorate FFP quality compared to a conventional system. Regardless of the thawing system, the postthaw refrigerated storage caused a decrease in several clotting factors and inhibitors (factors V, VIII, and IX; von Willebrand factor activity; protein S and C activity) and a significant increase of factor XI.

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

BACKGROUND

The major aims of the RBC-Omics study were to evaluate the genomic and metabolomic determinants of spontaneous and stress-induced hemolysis during RBC storage. This study was unique in scale and design to allow evaluation of RBC donations from a sufficient number of donors across the spectrum of race, ethnicity, sex, and donation intensity. Study procedures were carefully piloted, optimized, and controlled to enable high-quality data collection.

METHODS

The enrollment goal of 14,000 RBC donors across four centers, with characterization of RBC hemolysis across two testing laboratories, required rigorous piloting and optimization and establishment of a quality assurance (QA) and quality control (QC) program. Optimization of WBC elution from leukoreduction (LR) filters, development and validation of small-volume transfer bags, impact of manufacturing and sample-handling procedures on hemolysis parameters, and testing consistency across laboratories and technicians and over time were part of this quality assurance/quality control program.

RESULTS

LR filter elution procedures were optimized for obtaining DNA for analysis. Significant differences between standard and pediatric storage bags led to use of an alternative LR-RBC transfer bag. The impact of sample preparation and freezing methods on metabolomics analyses was evaluated. Proficiency testing monitored and documented testing consistency across laboratories and technicians.

CONCLUSION

Piloting and optimization, and establishment of a robust quality assurance/quality control program documented process consistency throughout the study and was essential in executing this large-scale multicenter study. This program supports the validity of the RBC-Omics study results and a sample repository that can be used in future studies.

TACO and TRALI: biology, risk factors, and prevention strategies

Transfusion-related acute lung injury (TRALI) and transfusion-associated circulatory overload (TACO) are the leading causes of transfusion-related morbidity and mortality. These adverse events are characterized by acute pulmonary edema within 6 hours of a blood transfusion and have historically been difficult to study due to underrecognition and nonspecific diagnostic criteria. However, in the past decade, in vivo models and clinical studies utilizing active surveillance have advanced our understanding of their epidemiology and pathogenesis. With the adoption of mitigation strategies and patient blood management, the incidence of TRALI and TACO has decreased. Continued research to prevent and treat these severe cardiopulmonary events is focused on both the blood component and the transfusion recipient.

Evaluation of Coagulation Factors Activity in Different Types of Plasma Preparations

Fresh frozen plasma (FFP) is a crucial substitute therapy in management of bleeding; producing plasma from whole blood stored within 24 h offers operational flexibility and leukocyte filtration significantly reduce transfusion reactions, it is necessary to consider the impact of these plasma preparations on clotting factors activity. Total of 75 plasma samples collected from 25 blood donors distributed as 3 groups; FFP (Group A), leukocyte filtrated FFP (Group B) and plasma frozen within 24 h i.e. PF24 (Group C), for all samples prothrombin time (PT), INR, (APTT), Factors V, VII, VIII, IX levels and Fibrinogen were done, also comparing coagulation factors levels in FFP in different blood groups. There were significant difference between three groups in (PT), INR and (APTT): (P = 0.00). Concerning Factor VII: significant difference (P = 0.03) between the three groups, FFP had a significantly higher level of FVII compared to filtrated FFP (98.92 vs. 82.52%; P = 0.02), while no significant difference between FFP and PF24 was detected (P = 0.76). Factor VIII: had significant difference (P = 0.00) between the three groups, FFP and Filtrated FFP had no significant difference regarding level of FVIII (P = 0.72), but FFP had significantly higher level of FVIII compared to PF24 (P < 0.05). Concerning Fibrinogen level: no significant difference between FFP and filtrated FFP (P = 0.99), while FFP had a higher level versus PF24 (P < 0.05). On the Contrary, no significant difference between three groups in Factor V: (P = 0.22) and Factor IX: (P = 0.12). ABO blood group effect on studied parameters in FFP: FVIII was statistically higher in Non-O blood group (P = 0.03), other factors had no statistical differences (P > 0.05). The leukocyte filtration of FFP did not affect the majority of coagulation factors activities, although FVII level was reduced, it stills enough for surgical hemostasis. The PF24 resulted in reduced FVIII and fibrinogen levels but no significant changes in FV, FVII or FIX, thus, can be used for FFP indications except that specifically requiring replacement of FVIII and/or fibrinogen as Hemophilia or DIC. No significant difference in coagulation factors of FFP between O and non-O blood groups except FVIII that was reduced in O blood group.

Optimizing transfusion strategies in damage control resuscitation: current insights

From clinical and laboratory studies of specific coagulation defects induced by injury, damage control resuscitation (DCR) emerged as the most effective management strategy for hemorrhagic shock. DCR of the trauma patient who has sustained massive blood loss consists of 1) hemorrhage control; 2) permissive hypotension; and 3) the prevention and correction of trauma-induced coagulopathies, referred to collectively here as acute coagulopathy of trauma (ACOT). Trauma patients with ACOT have higher transfusion requirements, may eventually require massive transfusion, and are at higher risk of exsanguinating. Distinct impairments in the hemostatic system associated with trauma include acquired quantitative and qualitative platelet defects, hypocoagulable and hypercoagulable states, and dysregulation of the fibrinolytic system giving rise to hyperfibrinolysis or a phenomenon referred to as fibrinolytic shutdown. Furthermore, ACOT is a component of a systemic host defense dysregulation syndrome that bears several phenotypic features comparable with other acute systemic physiological insults such as sepsis, myocardial infarction, and postcardiac arrest syndrome. Progress in the science of resuscitation has been continuing at an accelerated rate, and clinicians who manage catastrophic blood loss may be incompletely informed of important advances that pertain to DCR. Therefore, we review recent findings that further characterize the pathophysiology of ACOT and describe the application of this new information to optimization of resuscitation strategies for the patient in hemorrhagic shock.

Cost estimate of platelet transfusion in the United States for patients with chronic liver disease and associated thrombocytopenia undergoing elective procedures

AIMS

This study aimed to estimate the cost of platelet transfusion in patients with chronic liver disease (CLD)-associated thrombocytopenia undergoing an elective procedure in the United States.

MATERIALS AND METHODS

The study was conducted in two parts: development of a conceptual framework identifying direct, indirect and intangible costs of platelet transfusion, followed by the estimation of the total cost of platelet transfusion in patients with CLD-associated thrombocytopenia before an elective procedure in the United States using the conceptual framework and cost data obtained from a literature search. The cost of the entire care required to raise a patient's platelet count before the procedure was considered.

RESULTS

The final conceptual framework included the costs of generating the supply of platelets, the platelet transfusion itself, adverse events associated with platelet transfusion and refractoriness to platelet transfusion. When costs were accounted for in all the framework cost categories, the total direct cost of a platelet transfusion in a patient with CLD and associated thrombocytopenia was estimated to be in the range of $5258 to $13,117 (2017 US dollars) in the United States. The largest portion of costs was incurred by the transfusion event itself ($3723 to $4436) and the cost of refractoriness ($874 to $7578), which included the opportunity cost of a delayed procedure and subsequent platelet transfusions with human leukocyte antigen-matched platelets.

LIMITATIONS AND CONCLUSIONS

Although we were unable to include all cost components identified in the conceptual framework in our total cost estimate, thus likely underestimating the true total cost, and despite the data gaps and challenges limiting our estimate of the full cost of a platelet transfusion in patients with CLD-associated thrombocytopenia undergoing an elective procedure in the United States, this study outlines a comprehensive conceptual framework for estimating the cost elements of a platelet transfusion in these patients.

Platelet transfusion: Current challenges

Since the late sixties, platelet concentrates are transfused to patients presenting with severe thrombocytopenia, platelet function defects, injuries, or undergoing surgery, to prevent the risk of bleeding or to treat actual hemorrhage. Current practices differ according to the country or even in different hospitals and teams. Although crucial advances have been made during the last decades, questions and debates still arise about the right doses to transfuse, the use of prophylactic or therapeutic strategies, the nature and quality of PC, the storage conditions, the monitoring of transfusion efficacy and the microbiological and immunological safety of platelet transfusion. Finally, new challenges are emerging with potential new platelet products, including cold stored or in vitro produced platelets. The most debated of these points are reviewed.

Blood and Blood Components: From Similarities to Differences

Blood transfusion is made possible because, in most countries and organizations, altruistic individuals voluntarily, anonymously, and generously donate (without compensation) either whole blood or separated components that are then processed and distributed by professionals, prior to being allocated to recipients in need. Being part of modern medicine, blood transfusion uses so-called standard blood components when relative to cellular fractions and fresh plasma. However, as will be discussed in this paper, strictly speaking, such so-called labile blood components are not completely standard. Furthermore, the prevalent system based on voluntary, non-remunerated blood donation is not yet universal and, despite claims by the World Health Organization that 100% of blood collection will be derived from altruistic donations by 2020 (postponed to 2025), many obstacles may hinder this ambition, especially when relative to the collection of the enormous amount of plasma destined for fractionation into plasma derivative or drugs. Finally, country organizations also vary due to the economy, sociology, politics, and epidemiology. This paper then, discusses the particulars (of which ethical considerations) of blood transfusion diversity and the consequences for donors, patients, and society.

Cold storage of platelets in platelet additive solution: an in vitro comparison of two Food and Drug Administration-approved collection and storage systems

BACKGROUND

Refrigeration of platelets (PLTs) in a PLT additive solution (PAS) reduces PLT activation compared to storage in plasma and preserves function for at least 15 days. Currently only two PASs are licensed by the Food and Drug Administration, each for use with only one apheresis platform. In this study, we compared the metabolic, functional, and activation status of PLTs collected on a Trima apheresis collection system and stored refrigerated in Isoplate (ISO) PAS to PLTs collected on an Amicus collection system and stored refrigerated in Intersol (INT) PAS.

STUDY DESIGN AND METHODS

Apheresis PLTs (n = 4-7 donors) were collected on a Trima in ISO PAS or on an Amicus in INT PAS. PLTs were stored in a walk-in refrigerator (1-6°C) without agitation for long-term storage. Bags were assayed at Days 1, 5, 10, and 15 of storage. Measurements included PLT counts, pH, aggregation response, rotational thromboelastometry, and activation markers.

RESULTS

Cold-stored Trima-collected PLTs in ISO were slightly more hemostatic than Amicus-collected PLTs in INT and displayed better adhesion to collagen under flow conditions. Amicus-collected PLTs in INT showed increased microaggregate formation on Days 5 and 10 and a significant decrease in PLT count over storage. Trima-collected PLTs in ISO displayed better clot strength than Amicus-collected PLTs in INT.

CONCLUSION

Compared to cold-stored Amicus PLTs in INT, Trima PLTs in ISO display superior in vitro function and may be better suited for treatment of bleeding patients. Clinical studies are warranted to confirm these findings.

Characteristics of Extracellular Vesicles in Red Blood Concentrates Change with Storage Time and Blood Manufacturing Method

Background

Extracellular vesicles (EVs) in blood products are potential effectors of inflammation and coagulation after transfusion. The aim of this study was to assess the impact of different blood manufacturing methods and duration of hypothermic storage on the EV subpopulations in relation to other in vitro quality parameters of red blood cell concentrate (RCC) products.

Methods

RCCs were produced using whole blood filtration (WBF) or red cell filtration (RCF) (n = 12/method), refrigerated for 43 days, and evaluated for EV size profile and concentration, red cell deformability, ATP and 2,3-DPG, hemolysis, and hematological indices.

Results

The total number of EVs increased significantly with storage in both methods, and WBF-RCCs contained the higher numbers of EVs compared to RCF-RCCs. The concentration of small EVs was greater in WBF-RCCs versus RCF-RCCs, with difference between the two methods observed on day 43 of storage (p = 0.001). Throughout storage, significant decreases were identified in ATP, 2,3-DPG, and EI_max, while an increase in hemolysis was observed in both RCC products.

Conclusion

The dynamic shift in the size and concentration of the EV subpopulations is dependent on the blood manufacturing method and length of storage. Better understanding of the potential clinical implications of these heterogeneous populations of EVs are needed.

The corneal epitheliotrophic abilities of lyophilized powder form human platelet lysates

Purpose

To evaluate whether lyophilized human platelet lysate (HPL) powder can preserve the growth factor concentrations and epitheliotrophic properties of liquid HPL, and potentially be used as a clinically-friendly treatment option.

Methods

Two commercialized liquid HPLs, UltraGRO TM (Helios, Atlanta, GA) and PLTMax (Mill Creek, Rochester, MI), were obtained and converted to lyophilized powder. After redissolution, lyophilized powder HPLs were compared with liquid HPLs, as well as human peripheral serum (HPS) and fetal bovine serum (FBS) in liquid or redissolved lyophilized powder forms. Concentrations of epidermal growth factor (EGF), transforming growth factor-β1 (TGF-β1), platelet-derived growth factor-AB (PDGF-AB) and platelet-derived growth factor-BB (PDGF-BB) were evaluated by enzyme-linked immunosorbent assay (ELISA). Human corneal epithelial cell line was incubated with the blood derivatives and evaluated for cell migration with scratch-induced directional wounding and proliferation with MTS assays. Cell differentiation was examined by transepithelial electrical resistance (TEER). Fluorescein staining and in vivo confocal microscopy were used to evaluate in vivo corneal epithelial wound healing in Sprague-Dawley rats that underwent corneal debridement and topical application of liquid and redissolved powder HPLs.

Results

Liquid form and redissolved lyophilized powder form HPLs had similar concentrations of EGF, TGF-β1, PDGF-AB and PDGF-BB. In vitro experiments on cell migration, proliferation and differentiation and rat models on wound healing demonstrated no significant difference between the liquid and redissolved lyophilized powder forms for HPLs, HPS and FBS. In vivo confocal microscopy revealed similar wound healing process at different layers of cornea after corneal epithelial debridement between liquid form and redissolved lyophilized power form of HPLs.

Conclusions

The redissolved lyophilized powder form of both commercialized HPLs showed similar growth factor concentrations and corneal epitheliotrophic abilities compared to the liquid form. Results suggest that the properties of liquid HPLs can be retained despite lyophilization and that lyophilized HPLs can be a treatment option for corneal epithelial disorders.

Intravenous synthetic platelet (SynthoPlate) nanoconstructs reduce bleeding and improve 'golden hour' survival in a porcine model of traumatic arterial hemorrhage

Traumatic non-compressible hemorrhage is a leading cause of civilian and military mortality and its treatment requires massive transfusion of blood components, especially platelets. However, in austere civilian and battlefield locations, access to platelets is highly challenging due to limited supply and portability, high risk of bacterial contamination and short shelf-life. To resolve this, we have developed an I.V.-administrable 'synthetic platelet' nanoconstruct (SynthoPlate), that can mimic and amplify body's natural hemostatic mechanisms specifically at the bleeding site while maintaining systemic safety. Previously we have reported the detailed biochemical and hemostatic characterization of SynthoPlate in a non-trauma tail-bleeding model in mice. Building on this, here we sought to evaluate the hemostatic ability of SynthoPlate in emergency administration within the 'golden hour' following traumatic hemorrhagic injury in the femoral artery, in a pig model. We first characterized the storage stability and post-sterilization biofunctionality of SynthoPlate in vitro. The nanoconstructs were then I.V.-administered to pigs and their systemic safety and biodistribution were characterized. Subsequently we demonstrated that, following femoral artery injury, bolus administration of SynthoPlate could reduce blood loss, stabilize blood pressure and significantly improve survival. Our results indicate substantial promise of SynthoPlate as a viable platelet surrogate for emergency management of traumatic bleeding.

Mechanisms of red blood cell transfusion-related immunomodulation

Red blood cell (RBC) transfusion is common in critically ill, postsurgical, and posttrauma patients in whom both systemic inflammation and immune suppression are associated with adverse outcomes. RBC products contain a multitude of immunomodulatory mediators that interact with and alter immune cell function. These interactions can lead to both proinflammatory and immunosuppressive effects. Defining clinical outcomes related to immunomodulatory effects of RBCs in transfused patients remains a challenge, likely due to complex interactions between individual blood product characteristics and patient-specific risk factors. Unpacking these complexities requires an in-depth understanding of the mechanisms of immunomodulatory effects of RBC products. In this review, we outline and classify potential mediators of RBC transfusion-related immunomodulation and provide suggestions for future research directions.

Amotosalen-inactivated plasma is as equally well tolerated as quarantine plasma in patients undergoing large volume therapeutic plasma exchange

A retrospective - single center - survey compared tolerance of individual donor therapeutic plasma in a series of 88 patients principally presenting with thrombotic microangiopathy; all patients underwent therapeutic plasma exchange (TPE) performed with more than 90% of either of two types of plasma preparations. One plasma type used in TPE was prepared with pathogen reduction by amotosalen addition and UVA illumination, and the other one was non-manipulated (quarantine plasma). Both types of plasma were single donor. Occurrences of adverse reactions were equally low in either arm (amotosalen: 9 in 4689 bags of ∼200mL [0.019] versus quarantine: 2 in 828 bags [0.024]), confirming the safe use of amotosalen inactivated therapeutic plasma for TPE.

Impact of technical and assay variation on reporting of hemolysis in stored red blood cell products

BACKGROUND

Hemolysis of RBCs is an important measure of product quality and is influenced by donor factors, blood component manufacturing and storage. Percent hemolysis is determined using hematocrit (Hct), supernatant Hb (SHb) and total Hb (THb), each of which can be measured using a variety of methods.

METHODS

Sixteen members of an international collaborative were surveyed to understand equipment and procedural variation in hemolysis testing. In a laboratory-based evaluation, we examined how hemolysis was impacted by: measurement of Hct, SHb, THb and number and force of centrifugations for SHb preparation. The number and size of extracellular vesicles (EVs) was also examined.

RESULTS

There was no consensus in equipment or procedures used by international laboratories to measure hemolysis. The centrifugation force used to prepare samples influenced SHb concentration when a single or double (p=0.0001) centrifugation step was used. The number and force of centrifugation related directly to the ability to remove EVs and EV-bound Hb from samples. Hemolysis varied significantly from 0.16% to 0.32% (mean of 0.22%) depending on the combination of methods or centrifugation conditions used to test expired samples.

CONCLUSION

Method and preparative procedures have a critical impact on measurement of hemolysis in RCC.

Redox Proteomics and Platelet Activation: Understanding the Redox Proteome to Improve Platelet Quality for Transfusion

Blood banks use pathogen inactivation (PI) technologies to increase the safety of platelet concentrates (PCs). The characteristics of PI-treated PCs slightly differ from those of untreated PCs, but the underlying reasons are not well understood. One possible cause is the generation of oxidative stress during the PI process. This is of great interest since reactive oxygen species (ROS) act as second messengers in platelet functions. Furthermore, there are links between protein oxidation and phosphorylation, another mechanism that is critical for cell regulation. Current research efforts focus on understanding the underlying mechanisms and identifying new target proteins. Proteomics technologies represent powerful tools for investigating signaling pathways involving ROS and post-translational modifications such as phosphorylation, while quantitative techniques enable the comparison of the platelet resting state versus the stimulated state. In particular, redox cysteine is a key player in platelet activation upon stimulation by different agonists. This review highlights the experiments that have provided insights into the roles of ROS in platelet function and the implications for platelet transfusion, and potentially in diseases such as inflammation and platelet hyperactivity. The review also describes the implication of redox mechanism in platelet storage considerations.